https://bugs.freedesktop.org/show_bug.cgi?id=29109
When configured with --disable-mitshm the symbols declared in shmint.h
do not exist. By guarding the include with '#ifdef MITSHM' these
symbols are skipped when generating sdksyms.c with --disable-mitshm.
Signed-off-by: Michael Olbrich <m.olbrich@pengutronix.de>
Reviewed-by: Jeremy Huddleston <jeremyhu@apple.com>