MAINTAINERS: Update my e-mail

Old e-mail address doesn't work anymore, update it to new one.

Link: https://lore.kernel.org/r/20210505173335.1483575-1-jernej.skrabec@gmail.com


Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>