(try3-resend) Fix nfs_compat_user_ino64 so it doesn't cause problems if bit 31 or...

(try3-resend) Fix nfs_compat_user_ino64 so it doesn't cause problems if bit 31 or 63 are set in fileid

The problem was use of an int32, which when converted to a uint64
is sign extended resulting in a fileid that doesn't fit in 32 bits
even though the intent of the function is to fit the fileid into
32 bits.

Signed-off-by: Frank Filz <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
[Trond: Added an include for compat.h]
Signed-off-by: Trond Myklebust <[email protected]>