mailmap: update Javier Martinez Canillas' email

The get_maintainer script still reports my old Collabora email based on
old commits but that address no longer exist so update mailmap to report
my current email and avoid people sending to the old address.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>