Cygwin: Drop looking for w32api in winsup/w32api

Stop looking for w32api headers in the (no longer existent)
winsup/w32api directory (removed in commit 61746d6ae8).

winsup/acinclude.m4

@@ -50,8 +50,6 @@ if test -n "$with_windows_headers"; then
     else
 	AC_MSG_ERROR([cannot find windef.h in specified --with-windows-headers path: $saw_windows_headers]);
     fi
-elif test -d "$winsup_srcdir/w32api/include/windef.h"; then
-    windows_headers="$winsup_srcdir/w32api/include"
 else
     windows_headers=$(cd $($ac_cv_prog_CC -xc /dev/null -E -include windef.h 2>/dev/null | sed -n 's%^# 1 "\([^"]*\)/windef\.h".*$%\1%p' | head -n1) 2>/dev/null && pwd)
     if test -z "$windows_headers" -o ! -d "$windows_headers"; then

winsup/configure

@@ -3430,8 +3430,6 @@ if test -n "$with_windows_headers"; then
     else
 	as_fn_error $? "cannot find windef.h in specified --with-windows-headers path: $saw_windows_headers" "$LINENO" 5;
     fi
-elif test -d "$winsup_srcdir/w32api/include/windef.h"; then
-    windows_headers="$winsup_srcdir/w32api/include"
 else
     windows_headers=$(cd $($ac_cv_prog_CC -xc /dev/null -E -include windef.h 2>/dev/null | sed -n 's%^# 1 "\([^"]*\)/windef\.h".*$%\1%p' | head -n1) 2>/dev/null && pwd)
     if test -z "$windows_headers" -o ! -d "$windows_headers"; then

winsup/cygserver/aclocal.m4

@@ -64,8 +64,6 @@ if test -n "$with_windows_headers"; then
     else
 	AC_MSG_ERROR([cannot find windef.h in specified --with-windows-headers path: $saw_windows_headers]);
     fi
-elif test -d "$winsup_srcdir/w32api/include/windef.h"; then
-    windows_headers="$winsup_srcdir/w32api/include"
 else
     windows_headers=$(cd $($ac_cv_prog_CC -xc /dev/null -E -include windef.h 2>/dev/null | sed -n 's%^# 1 "\([^"]*\)/windef\.h".*$%\1%p' | head -n1) 2>/dev/null && pwd)
     if test -z "$windows_headers" -o ! -d "$windows_headers"; then

winsup/cygserver/configure

@@ -3431,8 +3431,6 @@ if test -n "$with_windows_headers"; then
     else
 	as_fn_error $? "cannot find windef.h in specified --with-windows-headers path: $saw_windows_headers" "$LINENO" 5;
     fi
-elif test -d "$winsup_srcdir/w32api/include/windef.h"; then
-    windows_headers="$winsup_srcdir/w32api/include"
 else
     windows_headers=$(cd $($ac_cv_prog_CC -xc /dev/null -E -include windef.h 2>/dev/null | sed -n 's%^# 1 "\([^"]*\)/windef\.h".*$%\1%p' | head -n1) 2>/dev/null && pwd)
     if test -z "$windows_headers" -o ! -d "$windows_headers"; then

winsup/cygwin/aclocal.m4

@@ -63,8 +63,6 @@ if test -n "$with_windows_headers"; then
     else
 	AC_MSG_ERROR([cannot find windef.h in specified --with-windows-headers path: $saw_windows_headers]);
     fi
-elif test -d "$winsup_srcdir/w32api/include/windef.h"; then
-    windows_headers="$winsup_srcdir/w32api/include"
 else
     windows_headers=$(cd $($ac_cv_prog_CC -xc /dev/null -E -include windef.h 2>/dev/null | sed -n 's%^# 1 "\([^"]*\)/windef\.h".*$%\1%p' | head -n1) 2>/dev/null && pwd)
     if test -z "$windows_headers" -o ! -d "$windows_headers"; then

winsup/cygwin/configure

@@ -3442,8 +3442,6 @@ if test -n "$with_windows_headers"; then
     else
 	as_fn_error $? "cannot find windef.h in specified --with-windows-headers path: $saw_windows_headers" "$LINENO" 5;
     fi
-elif test -d "$winsup_srcdir/w32api/include/windef.h"; then
-    windows_headers="$winsup_srcdir/w32api/include"
 else
     windows_headers=$(cd $($ac_cv_prog_CC -xc /dev/null -E -include windef.h 2>/dev/null | sed -n 's%^# 1 "\([^"]*\)/windef\.h".*$%\1%p' | head -n1) 2>/dev/null && pwd)
     if test -z "$windows_headers" -o ! -d "$windows_headers"; then

winsup/utils/aclocal.m4

@@ -63,8 +63,6 @@ if test -n "$with_windows_headers"; then
     else
 	AC_MSG_ERROR([cannot find windef.h in specified --with-windows-headers path: $saw_windows_headers]);
     fi
-elif test -d "$winsup_srcdir/w32api/include/windef.h"; then
-    windows_headers="$winsup_srcdir/w32api/include"
 else
     windows_headers=$(cd $($ac_cv_prog_CC -xc /dev/null -E -include windef.h 2>/dev/null | sed -n 's%^# 1 "\([^"]*\)/windef\.h".*$%\1%p' | head -n1) 2>/dev/null && pwd)
     if test -z "$windows_headers" -o ! -d "$windows_headers"; then

winsup/utils/configure

@@ -3137,8 +3137,6 @@ if test -n "$with_windows_headers"; then
     else
 	as_fn_error $? "cannot find windef.h in specified --with-windows-headers path: $saw_windows_headers" "$LINENO" 5;
     fi
-elif test -d "$winsup_srcdir/w32api/include/windef.h"; then
-    windows_headers="$winsup_srcdir/w32api/include"
 else
     windows_headers=$(cd $($ac_cv_prog_CC -xc /dev/null -E -include windef.h 2>/dev/null | sed -n 's%^# 1 "\([^"]*\)/windef\.h".*$%\1%p' | head -n1) 2>/dev/null && pwd)
     if test -z "$windows_headers" -o ! -d "$windows_headers"; then