brcmfmac: sdio: remove unused variable retry_limit

retry_limit has never been used during the life of this driver, so
we may as well remove it as it is redundant.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Julian Calaby <julian.calaby@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

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

@@ -535,9 +535,6 @@ static int qcount[NUMPRIO];
 
 #define RETRYCHAN(chan) ((chan) == SDPCM_EVENT_CHANNEL)
 
-/* Retry count for register access failures */
-static const uint retry_limit = 2;
-
 /* Limit on rounding up frames */
 static const uint max_roundup = 512;