[MIPS] Drop __ARCH_WANT_SYS_FADVISE64

sys_fadvise64() is not used on MIPS.  The libc can implement
both posix_fadvise() and posix_fadvise64() using sys_fadvise64_64().
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

include/asm-mips/unistd.h

@@ -949,7 +949,6 @@
 #define __ARCH_WANT_SYS_UTIME
 #define __ARCH_WANT_SYS_WAITPID
 #define __ARCH_WANT_SYS_SOCKETCALL
-#define __ARCH_WANT_SYS_FADVISE64
 #define __ARCH_WANT_SYS_GETPGRP
 #define __ARCH_WANT_SYS_LLSEEK
 #define __ARCH_WANT_SYS_NICE