Drop MINGW_FE, which I can't find any trace of, and instead detect and
use MinGW compilers.
This requires adding AC_CANONICAL_TARGET, to set $target_cpu.
* cygload/cygload.cc: Move to winsup.api. Add comments from README.
* cygload/cygload.h: Move to winsup.api.
* cygload/cygload.exp: Move to winsup.api.
* Makefile.in: Remove cygload.
* winsup.api/winsup.exp: If a .exp file is detected, run it rather than using
standard compile.
* winsup.api/resethand.c (main): Use printf to print status or expect thinks
something is wrong.