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: Arend Van Spriel <arend@broadcom.com>
Reviewed-by: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: Daniel (Deognyoun) Kim <dekim@broadcom.com>
Signed-off-by: Hante Meuleman <meuleman@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Kalle 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;
 }