Currently libatomic, libgfortran, libgomp, and libitm have a version
of the CHECK_ATTRIBUTE_VISIBILITY macro.
Put the macro in its own file and have all libraries use it.
config/ChangeLog:
* visibility.m4: New file.
libatomic/ChangeLog:
* Makefile.in: Regenerate.
* acinclude.m4: Delete LIBAT_CHECK_ATTRIBUTE_VISIBILITY.
* aclocal.m4: Regenerate.
* configure: Likewise.
* configure.ac: Use GCC_CHECK_ATTRIBUTE_VISIBILITY instead of
LIBAT_CHECK_ATTRIBUTE_VISIBILITY.
* testsuite/Makefile.in: Regenerate.
libgfortran/ChangeLog:
* Makefile.in: Regenerate.
* acinclude.m4: Delete LIBGFOR_CHECK_ATTRIBUTE_VISIBILITY.
* aclocal.m4: Regenerate.
* configure: Likewise.
* configure.ac: Use GCC_CHECK_ATTRIBUTE_VISIBILITY istead of
LIBGFOR_CHECK_ATTRIBUTE_VISIBILITY.
libgomp/ChangeLog:
* Makefile.in: Regenerate.
* acinclude.m4: Delete LIGOMP_CHECK_ATTRIBUTE_VISIBILITY.
* aclocal.m4: Regenerate.
* configure: Likewise.
* configure.ac: Use GCC_CHECK_ATTRIBUTE_VISIBILITY instead of
LIGOMP_CHECK_ATTRIBUTE_VISIBILITY.
* testsuite/Makefile.in: Regenerate.
libitm/ChangeLog:
* Makefile.in: Regenerate.
* acinclude.m4: Delete LIBITM_CHECK_ATTRIBUTE_VISIBILITY.
* aclocal.m4: Regenerate.
* configure: Likewise.
* configure.ac: Use GCC_CHECK_ATTRIBUTE_VISIBILITY instead of
LIBITM_CHECK_ATTRIBUTE_VISIBILITY.
* testsuite/Makefile.in: Regenerate.
Signed-off-by: Pietro Monteiro <pietro@sociotechnical.xyz>