ipg: endianness fixes

if your mask is host-endian, you should apply it after le64_to_cpu();
if it's little-endian - before.  Doing both (for the same mask and
little-endian value) is broken.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>