brcmfmac: Fix iovar 'bw_cap' set command failure

Fix iovar 'bw_cap' set command failure introduced by

  commit ff3b0fba6f25555ef59c55d138a467d0f81d82d7
  Author: Arend van Spriel <arend@broadcom.com>
  Date:   Sat Mar 15 12:00:57 2014 +0100

      brcmfmac: fallback to mimo_bw_cap for older firmwares

This resulted in disabling 20MHz operation in the firmware.
Reviewed-by: Arend Van Spriel <arend@broadcom.com>
Signed-off-by: Daniel Kim <dekim@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c

@@ -4948,7 +4948,7 @@ static int brcmf_enable_bw40_2g(struct brcmf_if *ifp)
 	if (!err) {
 		/* only set 2G bandwidth using bw_cap command */
 		band_bwcap.band = cpu_to_le32(WLC_BAND_2G);
-		band_bwcap.bw_cap = cpu_to_le32(WLC_BW_40MHZ_BIT);
+		band_bwcap.bw_cap = cpu_to_le32(WLC_BW_CAP_40MHZ);
 		err = brcmf_fil_iovar_data_set(ifp, "bw_cap", &band_bwcap,
 					       sizeof(band_bwcap));
 	} else {