Consistent macro naming for macros that use GCC __attribute__.

Consistent macro naming for macros that use GCC __attribute__.

* lib/di-set.h (_GL_ATTRIBUTE_NONNULL): Renamed from
_ATTRIBUTE_NONNULL_.
* lib/ino-map.h (_GL_ATTRIBUTE_NONNULL): Likewise.
* lib/hash.h (_GL_ATTRIBUTE_WUR): Renamed from ATTRIBUTE_WUR.
* lib/ignore-value.h (_GL_ATTRIBUTE_DEPRECATED): Renamed from
ATTRIBUTE_DEPRECATED.
* lib/openat.h (_GL_ATTRIBUTE_NORETURN): Renamed from
ATTRIBUTE_NORETURN.
* lib/sigpipe-die.h (_GL_ATTRIBUTE_NORETURN): Likewise.
* lib/xmemdup0.h (_GL_ATTRIBUTE_NORETURN): Likewise.
* lib/xstrtol.h (_GL_ATTRIBUTE_NORETURN): Likewise.
* lib/xalloc.h (_GL_ATTRIBUTE_NORETURN): Likewise.
(_GL_ATTRIBUTE_MALLOC): Renamed from ATTRIBUTE_MALLOC.
(_GL_ATTRIBUTE_ALLOC_SIZE): Renamed from ATTRIBUTE_ALLOC_SIZE.
* lib/version-etc.h (_GL_ATTRIBUTE_SENTINEL): Renamed from
ATTRIBUTE_SENTINEL.
* lib/safe-alloc.h (_GL_ATTRIBUTE_RETURN_CHECK): Renamed from
ATTRIBUTE_RETURN_CHECK.
* tests/test-ignore-value.c (_GL_ATTRIBUTE_RETURN_CHECK): Likewise.
* tests/test-argmatch.c (_GL_ATTRIBUTE_NORETURN): Renamed from
ATTRIBUTE_NORETURN.
* tests/test-exclude.c (_GL_ATTRIBUTE_NORETURN): Likewise.
Reported by Paul Eggert.