qcacld-3.0: disa: Replace explicit comparison to NULL

Per the Linux Kernel coding style, as enforced by the kernel
checkpatch script, pointers should not be explicitly compared to
NULL. Therefore within disa replace any such comparisons with logical
operations performed on the pointer itself.

Change-Id: Id25e4748819d206e361a55532a5ccfd648744b15
CRs-Fixed: 2418403
2 files changed