qcacld-3.0: Fix potential buffer overflow
In the function sap_clear_session_param, sapctx->sessionId can have
value more than max value allowed for the array
mac_ctx->sap.sapCtxList.
Add sanity check for the variable sapctx->sessionId
Change-Id: I846a8a1435de63d0a2e34f23bc407e0a8fa53eb2
CRs-Fixed: 2162255