mmap: Avoid the sanitizer configure check failure

mmap: Avoid the sanitizer configure check failure

When -fsanitize=address,undefined is used to build, the mmap configure
check failed with

=================================================================
==231796==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 4096 byte(s) in 1 object(s) allocated from:
    #0 0x7cdd3d0defdf in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:69
    #1 0x5750c7f6d72b in main /home/alan/build/gas-san/all/bfd/conftest.c:239

Direct leak of 4096 byte(s) in 1 object(s) allocated from:
    #0 0x7cdd3d0defdf in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:69
    #1 0x5750c7f6d2e1 in main /home/alan/build/gas-san/all/bfd/conftest.c:190

SUMMARY: AddressSanitizer: 8192 byte(s) leaked in 2 allocation(s).

Replace AC_FUNC_MMAP with GCC_AC_FUNC_MMAP to avoid the sanitizer
configure check failure.

bfd/

	* configure.ac: Replace AC_FUNC_MMAP with GCC_AC_FUNC_MMAP.
	* Makefile.in: Regenerated.
	* aclocal.m4: Likewise.
	* configure: Likewise.

binutils/

	* configure.ac: Replace AC_FUNC_MMAP with GCC_AC_FUNC_MMAP.
	* Makefile.in: Regenerated.
	* aclocal.m4: Likewise.
	* configure: Likewise.

ld/

	* configure.ac: Replace AC_FUNC_MMAP with GCC_AC_FUNC_MMAP.
	* Makefile.in: Regenerated.
	* aclocal.m4: Likewise.
	* configure: Likewise.

libctf/

	* configure.ac: Replace AC_FUNC_MMAP with GCC_AC_FUNC_MMAP.
	* Makefile.in: Regenerated.
	* aclocal.m4: Likewise.
	* configure: Likewise.

libsframe/

	* configure.ac: Replace AC_FUNC_MMAP with GCC_AC_FUNC_MMAP.
	* Makefile.in: Regenerated.
	* aclocal.m4: Likewise.
	* configure: Likewise.