wlan: Return EOPNOTSUPP if fw_mem_dump is not supported

wlan_hdd_cfg80211_get_fw_mem_dump() currently returns EINVAL
if the feature is not supported by firmware. Return EOPNOTSUPP
instead of EINVAL, which looks more appropriate.

Change-Id: I1ca2ebd3fa572ba3caae29ef9f1e396693378fb2
CRs-Fixed: 2088667
diff --git a/CORE/HDD/src/wlan_hdd_cfg80211.c b/CORE/HDD/src/wlan_hdd_cfg80211.c
index 198384d..9590082 100644
--- a/CORE/HDD/src/wlan_hdd_cfg80211.c
+++ b/CORE/HDD/src/wlan_hdd_cfg80211.c
@@ -5870,7 +5870,7 @@
        (FALSE == sme_IsFeatureSupportedByFW(MEMORY_DUMP_SUPPORTED)))
     {
        hddLog(VOS_TRACE_LEVEL_INFO, FL("FW dump Logging not supported"));
-       return -EINVAL;
+       return -EOPNOTSUPP;
     }
     /*call common API for FW mem dump req*/
     ret = wlan_hdd_fw_mem_dump_req(pHddCtx);