net: remove dev_valid_name() check from __dev_alloc_name()

__dev_alloc_name() is only called by dev_prep_valid_name(),
which already checks that name is valid.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231023152346.3639749-6-kuba@kernel.org


Signed-off-by: Jakub Kicinski <kuba@kernel.org>