media: Makefiles: remove extra spaces

It is hard to keep all those options aligned as newer config
changes get added, and we really don't want to have patches adding
new options also touching already existing entries.

So, drop the extra spaces.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>