iw: cqm: check nlmsg_alloc() return

If nlmsg_alloc() fails, don't crash but return an error.

Signed-off-by: Amit Khatri <amit.khatri@samsung.com>
Signed-off-by: Rahul Jain <rahul.jain@samsung.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

cqm.c

@@ -34,6 +34,8 @@ static int iw_cqm_rssi(struct nl80211_state *state,
 
 	/* connection quality monitor attributes */
 	cqm = nlmsg_alloc();
+	if (!cqm)
+		return -ENOMEM;
 
 	NLA_PUT_U32(cqm, NL80211_ATTR_CQM_RSSI_THOLD, thold);
 	NLA_PUT_U32(cqm, NL80211_ATTR_CQM_RSSI_HYST, hyst);