brcmfmac: fweh: Remove set but unused variable 'err'

Fixes the following W=1 kernel build warning(s):

 drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c: In function ‘brcmf_fweh_handle_if_event’:
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c:131:6: warning: variable ‘err’ set but not used [-Wunused-but-set-variable]

Cc: Arend van Spriel <arend.vanspriel@broadcom.com>
Cc: Franky Lin <franky.lin@broadcom.com>
Cc: Hante Meuleman <hante.meuleman@broadcom.com>
Cc: Chi-Hsien Lin <chi-hsien.lin@cypress.com>
Cc: Wright Feng <wright.feng@cypress.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Cc: linux-wireless@vger.kernel.org
Cc: brcm80211-dev-list.pdl@broadcom.com
Cc: brcm80211-dev-list@cypress.com
Cc: netdev@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200814113933.1903438-23-lee.jones@linaro.org

drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c

@@ -128,7 +128,6 @@ static void brcmf_fweh_handle_if_event(struct brcmf_pub *drvr,
 	struct brcmf_if_event *ifevent = data;
 	struct brcmf_if *ifp;
 	bool is_p2pdev;
-	int err = 0;
 
 	brcmf_dbg(EVENT, "action: %u ifidx: %u bsscfgidx: %u flags: %u role: %u\n",
 		  ifevent->action, ifevent->ifidx, ifevent->bsscfgidx,
@@ -171,8 +170,8 @@ static void brcmf_fweh_handle_if_event(struct brcmf_pub *drvr,
 	if (ifp && ifevent->action == BRCMF_E_IF_CHANGE)
 		brcmf_proto_reset_if(drvr, ifp);
 
-	err = brcmf_fweh_call_event_handler(drvr, ifp, emsg->event_code, emsg,
-					    data);
+	brcmf_fweh_call_event_handler(drvr, ifp, emsg->event_code, emsg,
+				      data);
 
 	if (ifp && ifevent->action == BRCMF_E_IF_DEL) {
 		bool armed = brcmf_cfg80211_vif_event_armed(drvr->config);