tile: remove compat_sys_lookup_dcookie declaration to fix compile error

With commit d8d14bd0 ("fs/compat: fix lookup_dcookie() parameter
handling") I changed the type of the len parameter of the
lookup_dcookie() syscall.

However I missed that there was still a stale declaration in
arch/tile/..  which now causes a compile error on tile:

  In file included from fs/dcookies.c:28:0:
  include/linux/compat.h:425:17: error: conflicting types for 'compat_sys_lookup_dcookie'
  fs/dcookies.c:207:1: error: conflicting types for 'compat_sys_lookup_dcookie'

Simply remove the declaration in the tile architecture, which is only a
leftover from before the different compat lookup_dcookie() versions have
been merged.  The correct declaration is now in include/linux/compat.h

The build error was reported by Fenguang's build bot.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/tile/include/asm/compat.h

@@ -281,7 +281,6 @@ long compat_sys_pread64(unsigned int fd, char __user *ubuf, size_t count,
 			u32 dummy, u32 low, u32 high);
 long compat_sys_pwrite64(unsigned int fd, char __user *ubuf, size_t count,
 			 u32 dummy, u32 low, u32 high);
-long compat_sys_lookup_dcookie(u32 low, u32 high, char __user *buf, size_t len);
 long compat_sys_sync_file_range2(int fd, unsigned int flags,
 				 u32 offset_lo, u32 offset_hi,
 				 u32 nbytes_lo, u32 nbytes_hi);