qcacld-3.0: Fix function type for wdi_event_unsub

To address kernel control flow integrity (CFI) issues related to type
mismatch, correct the return type of wdi_event_unsub().

Change-Id: I45d090cb4011ca659e30b2f7be6c2b7d32bbba4b
CRs-Fixed: 2402957
2 files changed