brcmfmac: Fix escan timer causing oops.

In some rare circumstances the escan protection timer can expire
before the setup completed (due to long timeouts on IOCTL). This
patch avoids this situation by setting the timer after the setup
completed correctly.
Reviewed-by: NArend Van Spriel <arend@broadcom.com>
Reviewed-by: NFranky (Zhenhui) Lin <frankyl@broadcom.com>
Reviewed-by: NPieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: NDaniel (Deognyoun) Kim <dekim@broadcom.com>
Signed-off-by: NHante Meuleman <meuleman@broadcom.com>
Signed-off-by: NArend van Spriel <arend@broadcom.com>
Signed-off-by: NKalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/brcm80211/brcmfmac/cfg80211.c

@@ -1050,10 +1050,6 @@ brcmf_cfg80211_escan(struct wiphy *wiphy, struct brcmf_cfg80211_vif *vif,
 	if (vif == cfg->p2p.bss_idx[P2PAPI_BSSCFG_DEVICE].vif)
 		vif = cfg->p2p.bss_idx[P2PAPI_BSSCFG_PRIMARY].vif;
 
-	/* Arm scan timeout timer */
-	mod_timer(&cfg->escan_timeout, jiffies +
-			WL_ESCAN_TIMER_INTERVAL_MS * HZ / 1000);
-
 	escan_req = false;
 	if (request) {
 		/* scan bss */
@@ -1112,12 +1108,14 @@ brcmf_cfg80211_escan(struct wiphy *wiphy, struct brcmf_cfg80211_vif *vif,
 		}
 	}
 
+	/* Arm scan timeout timer */
+	mod_timer(&cfg->escan_timeout, jiffies +
+			WL_ESCAN_TIMER_INTERVAL_MS * HZ / 1000);
+
 	return 0;
 
 scan_out:
 	clear_bit(BRCMF_SCAN_STATUS_BUSY, &cfg->scan_status);
-	if (timer_pending(&cfg->escan_timeout))
-		del_timer_sync(&cfg->escan_timeout);
 	cfg->scan_request = NULL;
 	return err;
 }