D_HASH{MASK,BITS} are used once each, both in the same function (d_hash()).
At this point they are actively misguiding - they imply that values are
compiler constants, which is no longer true.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

(cherry picked from commit 482db906)
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>