net: phy: broadcom: drop brcm_phy_setbits() and use phy_set_bits() instead

net: phy: broadcom: drop brcm_phy_setbits() and use phy_set_bits() instead

Linux provides phy_set_bits() helper so let's drop brcm_phy_setbits() and
use phy_set_bits() in its place.

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20230622184721.24368-1-giulio.benetti@benettiengineering.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>