icnss2: Fix build issue when strict-prototypes is enabled

When strict-prototypes and format-insufficient-args are
enabled then icnss2 fails to build. Change prototype of
icnss_get_plat_priv() and remove extra arg from error log
in icnss_wlfw_wlan_mac_req_send_sync().

Change-Id: I81c7d90fa24b05d573a9ce47c0301d2798118182
CRs-Fixed: 3359853

icnss2/main.c

@@ -126,7 +126,7 @@ static void icnss_set_plat_priv(struct icnss_priv *priv)
 	penv = priv;
 }
 
-static struct icnss_priv *icnss_get_plat_priv()
+static struct icnss_priv *icnss_get_plat_priv(void)
 {
 	return penv;
 }