Add libaio to SUBLIBS built for Cygwin

Provide libaio.a for those projects (such as stress-ng) checking for
POSIX aio support by looking for this library at configure time.
A release note is provided for Cygwin 3.6.0.

Signed-off-by: Mark Geisert <mark@maxrnd.com>
Fixes: N/A (new code)

winsup/cygwin/Makefile.am

@@ -550,7 +550,8 @@ SUBLIBS = \
 	libresolv.a \
 	librt.a \
 	libacl.a \
-	libssp.a
+	libssp.a \
+	libaio.a
 
 noinst_LIBRARIES = \
 	libdll.a \
@@ -666,6 +667,9 @@ libacl.a: $(LIB_NAME) sec/posixacl.o
 libssp.a: $(LIB_NAME) $(wildcard $(newlib_build)/libc/ssp/*.o)
 	$(AM_V_GEN)$(speclib) $^ $(@F)
 
+libaio.a: $(LIB_NAME) aio.o
+	$(AM_V_GEN)$(speclib) $^ $(@F)
+
 #
 # all
 #

winsup/cygwin/release/3.6.0

@@ -13,6 +13,9 @@ What's new:
   Windows attributes FILE_ATTRIBUTE_PINNED and FILE_ATTRIBUTE_UNPINNED.
   Add matching 'p' and 'u' mode bits in chattr(1) and lsattr(1).
 
+- New libaio.a provided for projects checking for POSIX aio support
+  by looking for this library at configure time.
+
 
 What changed:
 -------------