[PATCH] freepgt: arch FIRST_USER_ADDRESS 0

Replace misleading definition of FIRST_USER_PGD_NR 0 by definition of
FIRST_USER_ADDRESS 0 in all the MMU architectures beyond arm and arm26.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>