wlan: Return an error code in case of invalid seq_len while adding key

There is no return statement in case of invalid sequence length in
__wlan_hdd_cfg80211_add_key api.

Return an error code in case of invalid seq_len.

Issue: SEC-1245
CRs-Fixed: 2153553
(adapted from commit https://source.codeaurora.org/quic/la/platform/vendor/qcom-opensource/wlan/prima
5a0eeb72c3cde7dcb8096967561a88a678ad9aec)
Signed-off-by: Gururaj Patil <gururaj.patil3@harman.com>
Change-Id: I10e1f5c193605dd76fa62b25e57f7957c19be373
diff --git a/drivers/staging/prima/CORE/HDD/src/wlan_hdd_cfg80211.c b/drivers/staging/prima/CORE/HDD/src/wlan_hdd_cfg80211.c
index 876f5d6..b962488 100644
--- a/drivers/staging/prima/CORE/HDD/src/wlan_hdd_cfg80211.c
+++ b/drivers/staging/prima/CORE/HDD/src/wlan_hdd_cfg80211.c
@@ -9012,6 +9012,8 @@
     {
         hddLog(VOS_TRACE_LEVEL_ERROR,"%s: Invalid seq length %d", __func__,
                 params->seq_len);
+
+        return -EINVAL;
     }
 
     hddLog(VOS_TRACE_LEVEL_INFO,