Define __ASSUME_ST_INO_64_BIT on all platforms.

	* sysdeps/unix/sysv/linux/alpha/kernel-features.h: #define
	  __ASSUME_ST_INO_64_BIT as 0
	* sysdeps/unix/sysv/linux/sh/kernel-features.h: Likewise.
	* sysdeps/unix/sysv/linux/fxstat64.c: Replace #ifdef with #if
	  over the code where __ASSUME_ST_INO_64_BIT is used.
	* sysdeps/unix/sysv/linux/lxstat64.c: Likewise.
	* sysdeps/unix/sysv/linux/xstat64.c: Likewise.
	* sysdeps/unix/sysv/linux/xstatconv.c: Likewise.