wcnss: add NULL check before accessing pnv pointer

Direct accessing of pnv pointer leads for NULL dereference.
To mitigate issue add NULL check before useing a pnv pointer.

Change-Id: Ia3cc5ee4e98f8ea658622c9bfff2c13d2e9cced1
CRs-Fixed: 790447
Signed-off-by: Anand N Sunkad <asunka@codeaurora.org>
2 files changed