prima: Validate TDLSSECONDARYCHANNELOFFSET command

Validate arguments for TDLSSECONDARYCHANNELOFFSET command
and return failure on invalid arguments.

Change-Id: I4e8d6633fc6b01ac4499a00e8712951d8fca6800
CRs-Fixed: 856495
diff --git a/CORE/HDD/src/wlan_hdd_main.c b/CORE/HDD/src/wlan_hdd_main.c
index 53567b9..5289784 100755
--- a/CORE/HDD/src/wlan_hdd_main.c
+++ b/CORE/HDD/src/wlan_hdd_main.c
@@ -4387,7 +4387,13 @@
            int set_value;
            /* Move pointer to ahead of TDLSOFFCH*/
            value += 26;
-           sscanf(value, "%d", &set_value);
+           if (!(sscanf(value, "%d", &set_value))) {
+               VOS_TRACE(VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_INFO,
+                               FL("No input identified"));
+               ret = -EINVAL;
+               goto exit;
+           }
+
            VOS_TRACE(VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_INFO,
                      "%s: Tdls offchannel offset:%d",
                      __func__, set_value);