Revert "ethtool: Fix mod state of verbose no_mask bitset"

Revert "ethtool: Fix mod state of verbose no_mask bitset"

This reverts commit 108a36d07c01edbc5942d27c92494d1c6e4d45a0.

It was reported that this fix breaks the possibility to remove existing WoL
flags. For example:
~$ ethtool lan2
...
        Supports Wake-on: pg
        Wake-on: d
...
~$ ethtool -s lan2 wol gp
~$ ethtool lan2
...
        Wake-on: pg
...
~$ ethtool -s lan2 wol d
~$ ethtool lan2
...
        Wake-on: pg
...

This worked correctly before this commit because we were always updating
a zero bitmap (since commit 6699170376ab ("ethtool: fix application of
verbose no_mask bitset"), that is) so that the rest was left zero
naturally. But now the 1->0 change (old_val is true, bit not present in
netlink nest) no longer works.

Reported-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reported-by: Michal Kubecek <mkubecek@suse.cz>
Closes: https://lore.kernel.org/netdev/20231019095140.l6fffnszraeb6iiw@lion.mk-sys.cz/
Cc: stable@vger.kernel.org
Fixes: 108a36d07c01 ("ethtool: Fix mod state of verbose no_mask bitset")
Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Link: https://lore.kernel.org/r/20231019-feature_ptp_bitset_fix-v1-1-70f3c429a221@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>