[PATCH V6 5/8] Add strstr to compressed string.c for ARM.

The shared efi-stub-helper.c functions require a strstr implementation. The EFI stub is part of the decompressor, so it does not use the kernel strstr() implementation. This patch adds a strstr() implementation to the string.c file for the decompressor, with the implementation copied from the

[PATCH V6 5/8] Add strstr to compressed string.c for ARM.

The shared efi-stub-helper.c functions require a strstr implementation. The EFI stub is part of the decompressor, so it does not use the kernel strstr() implementation. This patch adds a strstr() implementation to the string.c file for the decompressor, with the implementation copied from the