gnulib: stdint: Add support for Android.

* lib/stdint.in.h: When included from Bionic <sys/types.h>, just
include the system's <stdint.h>.
Reported by Simon Josefsson <simon@josefsson.org>.

Conflicts:
	ChangeLog
gnulib: stdint: Improve support for Android.

* lib/stdint.in.h: Test __ANDROID__, not __BIONIC__.
Reported by Simon Josefsson <simon@josefsson.org>.

Conflicts:
	ChangeLog
gnulib: stdint: fix build with Android's Bionic fox x86

* lib/stdint.in.h: fix check to test if included-fixed/sys/types.h
was already included as _SSIZE_T_DEFINED_ might also be defined
in include/machine/_types.h, which is included by stdio.h

Signed-off-by: Eric Blake <eblake@redhat.com>

Conflicts:
	ChangeLog