msm: bus: Don't call container_of on a NULL pointer
msm: bus: Don't call container_of on a NULL pointer

Calling container_of on a NULL pointer results in a
non-NULL value, causing downstream error handling to fail.

Change-Id: Ifa4b4003bb02e9f640f91b5190a8025d7ad2dd1d
Signed-off-by: Stepan Moskovchenko <4b3f23b045e38e54cffd83d34440316666b35af9@codeaurora.org>

TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas