s390: drop pte_file()-related helpers

s390: drop pte_file()-related helpers

commit 6e76d4b20bf6b514408ab5bd07f4a76723259b64 upstream.

We've replaced remap_file_pages(2) implementation with emulation.  Nobody
creates non-linear mapping anymore.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>