ar71xx: add missing tx gain table flag for buffalo wzr-hp-g450h

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

SVN-Revision: 39139

target/linux/ar71xx/patches-3.10/612-MIPS-ath79-set-buffalo-txgain.patch

+--- a/arch/mips/ath79/dev-wmac.c
++++ b/arch/mips/ath79/dev-wmac.c
+@@ -306,6 +306,11 @@ void __init ath79_wmac_disable_5ghz(void
+ 	ath79_wmac_data.disable_5ghz = true;
+ }
+ 
++void __init ath79_wmac_set_tx_gain_buffalo(void)
++{
++	ath79_wmac_data.tx_gain_buffalo = true;
++}
++
+ void __init ath79_register_wmac(u8 *cal_data, u8 *mac_addr)
+ {
+ 	if (soc_is_ar913x())
+--- a/arch/mips/ath79/dev-wmac.h
++++ b/arch/mips/ath79/dev-wmac.h
+@@ -16,6 +16,7 @@ void ath79_register_wmac(u8 *cal_data, u
+ void ath79_register_wmac_simple(void);
+ void ath79_wmac_disable_2ghz(void);
+ void ath79_wmac_disable_5ghz(void);
++void ath79_wmac_set_tx_gain_buffalo(void);
+ 
+ bool ar93xx_wmac_read_mac_address(u8 *dest);
+