lib/digsig: pkcs_1_v1_5_decode_emsa cleanup
lib/digsig: pkcs_1_v1_5_decode_emsa cleanup

Removed useless 'is_valid' variable in pkcs_1_v1_5_decode_emsa(),
which was inhereted from original code. Client now uses return value
to check for an error.

Signed-off-by: Dmitry Kasatkin <8adb5f95ce8fa26dbddb33bd46c9f98f39d4d75f@intel.com>
Reviewed-by: Tetsuo Handa <3d00b54ad717112934d0b63b7ac2975b44022a61@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <10d11de3abc355eabe955bb734f0f8e71da56e16@namei.org>

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