sysmacros major/minor: result should have type unsigned int, not dev_t

include/sys/sysmacros.h

@@ -1,8 +1,8 @@
 #ifndef _SYS_SYSMACROS_H
 #define _SYS_SYSMACROS_H
 
-#define major(x) (((x) >> 8) & 0xff)
-#define minor(x) ((x) & 0xff)
+#define major(x) ((unsigned)((x) >> 8) & 0xff)
+#define minor(x) ((unsigned)(x) & 0xff)
 #define makedev(x,y) (((x)<<8)|((y)&0xff))
 
 #endif