util: Fix open_image_ro definition

No colon at the end and handle empty ... set properly.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

include/crtools.h

@@ -103,7 +103,7 @@ extern int open_image_dir(void);
 extern void close_image_dir(void);
 
 int open_image(int type, unsigned long flags, ...);
-#define open_image_ro(type, ...) open_image(type, O_RDONLY, __VA_ARGS__);
+#define open_image_ro(type, ...) open_image(type, O_RDONLY, ##__VA_ARGS__)
 extern int open_image_ro_nocheck(const char *fmt, int pid);
 
 #define LAST_PID_PATH		"/proc/sys/kernel/ns_last_pid"