mesa/imports: let the build system detect strtok_r()

Closes: mesa/mesa#2013
Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Tested-by: Prodea Alexandru-Liviu <liviuprodea@yahoo.com>
Reviewed-by: Dylan Baker <dylan@pnwbakers.com>
49 jobs for !2612 with strtok_r in 47 seconds (queued for 6 seconds)
merge request