net: remove redundant 'depends on NET'

These Kconfig files are included from net/Kconfig, inside the
if NET ... endif.

Remove 'depends on NET', which we know it is already met.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20210125232026.106855-1-masahiroy@kernel.org


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