rt2800: 5592: early defines

Add basic defines for 5592 chip. It can not be enabled until
CONFIG_RT2800USB_RT55XX configuration option will be provided in the
Kconfig.

Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Tested-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 086abb4..4251835 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -193,6 +193,7 @@
 #define RT3883		0x3883	/* WSOC */
 #define RT5390		0x5390  /* 2.4GHz */
 #define RT5392		0x5392  /* 2.4GHz */
+#define RT5592		0x5592
 
 	u16 rf;
 	u16 rev;