GCC4.6: Convert various empty macros to inline functions

Fix the following gcc4.6 problems:

cmd_date.c: In function ‘do_date’:
cmd_date.c:50:6: warning: variable ‘old_bus’ set but not used
[-Wunused-but-set-variable]
asix.c: In function ‘asix_init’:
asix.c:317:6: warning: variable ‘rx_ctl’ set but not used
[-Wunused-but-set-variable]
usb.c: In function ‘usb_parse_config’:
usb.c:331:17: warning: variable ‘ch’ set but not used
[-Wunused-but-set-variable]
usb.c: In function ‘usb_hub_port_connect_change’:
usb.c:1123:29: warning: variable ‘portchange’ set but not used
[-Wunused-but-set-variable]
usb.c: In function ‘usb_hub_configure’:
usb.c:1183:25: warning: variable ‘hubsts’ set but not used
[-Wunused-but-set-variable]
usb_storage.c: In function ‘usb_stor_CB_reset’:
usb_storage.c:466:6: warning: variable ‘result’ set but not used
[-Wunused-but-set-variable]
Signed-off-by: NMarek Vasut <marek.vasut@gmail.com>

common/usb.c

@@ -63,7 +63,7 @@
 #ifdef	USB_DEBUG
 #define	USB_PRINTF(fmt, args...)	printf(fmt , ##args)
 #else
-#define USB_PRINTF(fmt, args...)
+static inline void USB_PRINTF(const char *fmt, ...) {}
 #endif
 
 #define USB_BUFSIZ	512
@@ -970,7 +970,7 @@ void usb_scan_devices(void)
 #ifdef	USB_HUB_DEBUG
 #define	USB_HUB_PRINTF(fmt, args...)	printf(fmt , ##args)
 #else
-#define USB_HUB_PRINTF(fmt, args...)
+static inline void USB_HUB_PRINTF(const char *fmt, ...) {}
 #endif
 
 

common/usb_storage.c

@@ -63,7 +63,7 @@
 #ifdef	USB_STOR_DEBUG
 #define USB_STOR_PRINTF(fmt, args...)	printf(fmt , ##args)
 #else
-#define USB_STOR_PRINTF(fmt, args...)
+static inline void USB_STOR_PRINTF(const char *fmt, ...) {}
 #endif
 
 #include <scsi.h>

include/common.h

@@ -120,8 +120,8 @@ typedef volatile unsigned char	vu_char;
 #define debug(fmt,args...)	printf (fmt ,##args)
 #define debugX(level,fmt,args...) if (DEBUG>=level) printf(fmt,##args);
 #else
-#define debug(fmt,args...)
-#define debugX(level,fmt,args...)
+static inline void debug(const char *fmt, ...) {}
+static inline void debugX(int level, const char *fmt, ...) {}
 #endif	/* DEBUG */
 
 #ifdef DEBUG

include/i2c.h

@@ -55,7 +55,10 @@
 #else
 #define CONFIG_SYS_MAX_I2C_BUS		1
 #define I2C_GET_BUS()		0
-#define I2C_SET_BUS(a)
+static inline int I2C_SET_BUS(unsigned int bus)
+{
+	return 0;
+}
 #endif
 
 /* define the I2C bus number for RTC and DTT if not already done */