rtl8xxxu: Add definitions for antenna selection registers for 8723BU

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_regs.h

@@ -756,6 +756,10 @@
 #define REG_FPGA1_RF_MODE		0x0900
 
 #define REG_FPGA1_TX_INFO		0x090c
+#define REG_DPDT_CTRL			0x092c	/* 8723BU */
+#define REG_RFE_CTRL_ANTA_SRC		0x0930	/* 8723BU */
+#define REG_RFE_PATH_SELECT		0x0940	/* 8723BU */
+#define REG_RFE_BUFFER			0x0944	/* 8723BU */
 
 #define REG_CCK0_SYSTEM			0x0a00
 #define  CCK0_SIDEBAND			BIT(4)