[ACPI] fix potential NULL dereference in acpi/video.c
[ACPI] fix potential NULL dereference in acpi/video.c

Found-by: Adrian Bunk <0b86548ef377da0031a3ff3f0c4e06f016e20105@stusta.de>
Signed-off-by: Len Brown <b060cfa1096cc6e8be83699ddb4ed8a77dd63af5@intel.com>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas