brcmfmac: Fix asymmetric IO functions.

Unlikely to be a problem, but brcmf_sdiod_regrl() is
not symmetric with brcmf_sdiod_regrb() in initializing
the data value on stack. Fix that.
Signed-off-by: Ian Molton <ian@mnementh.co.uk>
[arend: reword the commit message a bit]
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

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

@@ -383,7 +383,7 @@ u8 brcmf_sdiod_regrb(struct brcmf_sdio_dev *sdiodev, u32 addr, int *ret)
 
 u32 brcmf_sdiod_regrl(struct brcmf_sdio_dev *sdiodev, u32 addr, int *ret)
 {
-	u32 data = 0;
+	u32 data;
 	int retval;
 
 	brcmf_dbg(SDIO, "addr:0x%08x\n", addr);