wlan: Fix static issues in csrApiScan.c and csrApiRoam.c files .

In this issue pointers 'pScanRequest'and
'pCommand' are checked for null , but there
is no associated return statement.
As a part of this fix ,return if
'pScanRequest' and 'pCommand' is NULL
thereby avoid dereference.
Change-Id: I601274d49399aaa3539156c6565254a8f8828081
CRs-Fixed: 620447
(cherry picked from commit aa44f6dc4c09b8ee7bb30d1e2cd6937908c7494e)
diff --git a/CORE/SME/src/csr/csrApiScan.c b/CORE/SME/src/csr/csrApiScan.c
index f73a4bc..2ec4d1d 100644
--- a/CORE/SME/src/csr/csrApiScan.c
+++ b/CORE/SME/src/csr/csrApiScan.c
@@ -632,6 +632,7 @@
     {
         smsLog( pMac, LOGE, FL(" pScanRequest is NULL"));
         VOS_ASSERT(0);
+        return eHAL_STATUS_FAILURE ;
     }
 
     /* During group formation, the P2P client scans for GO with the specific SSID.