brcmsmac: Remove unnecessary parentheses

This patch fixes the clang warning of extraneous parentheses, with the
following coccinelle script.

@@
identifier i;
expression e;
statement s;
@@
if (
-(i == e)
+i == e
 )
s

Suggested-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Varsha Rao <rvarsha016@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_cmn.c

@@ -159,7 +159,7 @@ u16 read_radio_reg(struct brcms_phy *pi, u16 addr)
 {
 	u16 data;
 
-	if ((addr == RADIO_IDCODE))
+	if (addr == RADIO_IDCODE)
 		return 0xffff;
 
 	switch (pi->pubpi.phy_type) {