mwifiex: Remove duplicated REG_PORT definition

The REG_PORT is defined twice, so remove one of them.
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20201119101204.72fd5f0a@xhacker.debian

drivers/net/wireless/marvell/mwifiex/sdio.h

@@ -43,8 +43,6 @@
 #define BLOCK_MODE	1
 #define BYTE_MODE	0
 
-#define REG_PORT			0
-
 #define MWIFIEX_SDIO_IO_PORT_MASK		0xfffff
 
 #define MWIFIEX_SDIO_BYTE_MODE_MASK	0x80000000