net: phy: mscc: fix excluded_middle.cocci warnings

Condition !A || A && B is equivalent to !A || B.

Generated by: scripts/coccinelle/misc/excluded_middle.cocci

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: kernel test robot <lkp@intel.com>
Signed-off-by: Julia Lawall <julia.lawall@inria.fr>
Reviewed-by: Antoine Tenart <atenart@kernel.org>
Link: https://lore.kernel.org/r/alpine.DEB.2.22.394.2011161633240.2682@hadrien
Signed-off-by: Jakub Kicinski <kuba@kernel.org>