phy: mscc: Use PHY_ID_MATCH_VENDOR to minimize PHY ID table

All the PHY devices variants specified have the same mask and
hence can be simplified to one vendor look up for 0x00070400.
Any individual config can be identified by PHY_ID_MATCH_EXACT
in the respective structure.

Signed-off-by: Harini Katakam <harini.katakam@amd.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>