utils/alsa.m4: include <stdlib.h> for exit()

alsa-project/alsa-lib pull request #278 was opened from thesamesam:

Clang 16 makes -Wimplicit-function-declaration an error by default and it's easier to just explicitly include <stdlib.h> rather than hope the ALSA headers always have it.

Signed-off-by: Sam James sam@gentoo.org

Request URL : https://github.com/alsa-project/alsa-lib/pull/278 Patch URL : https://github.com/alsa-project/alsa-lib/pull/278.patch Repository URL: https://github.com/alsa-project/alsa-lib