MAINTAINERS: remove extra wireless section

There's an unneeded and almost empty wireless section in MAINTAINERS, seems to
be leftovers from commit 0e324cf6 ("MAINTAINERS: changes for wireless"). I
don't see any need for that so let's remove it.

Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220117181958.3509-2-kvalo@kernel.org