Having the users of MSCC_OCELOT_SWITCH_LIB depend on REGMAP_MMIO was a
bad idea, since that symbol is not user-selectable. So we should have
kept a 'select REGMAP_MMIO'.

When we do that, we run into 2 more problems:

- By depending on GENERIC_PHY, we are causing a recursive dependency.
  But it looks like GENERIC_PHY has no other dependencies, and other
  drivers select it, so we can select it too:

drivers/of/Kconfig:69:error: recursive dependency detected!
drivers/of/Kconfig:69:  symbol OF_IRQ depends on IRQ_DOMAIN
kernel/irq/Kconfig:68:  symbol IRQ_DOMAIN is selected by REGMAP
drivers/base/regmap/Kconfig:7:  symbol REGMAP default is visible depending on REGMAP_MMIO
drivers/base/regmap/Kconfig:39: symbol REGMAP_MMIO is selected by MSCC_OCELOT_SWITCH_LIB
drivers/net/ethernet/mscc/Kconfig:15:   symbol MSCC_OCELOT_SWITCH_LIB is selected by MSCC_OCELOT_SWITCH
drivers/net/ethernet/mscc/Kconfig:22:   symbol MSCC_OCELOT_SWITCH depends on GENERIC_PHY
drivers/phy/Kconfig:8:  symbol GENERIC_PHY is selected by PHY_BCM_NS_USB3
drivers/phy/broadcom/Kconfig:41:        symbol PHY_BCM_NS_USB3 depends on MDIO_BUS
drivers/net/phy/Kconfig:13:     symbol MDIO_BUS depends on MDIO_DEVICE
drivers/net/phy/Kconfig:6:      symbol MDIO_DEVICE is selected by PHYLIB
drivers/net/phy/Kconfig:254:    symbol PHYLIB is selected by ARC_EMAC_CORE
drivers/net/ethernet/arc/Kconfig:19:    symbol ARC_EMAC_CORE is selected by ARC_EMAC
drivers/net/ethernet/arc/Kconfig:25:    symbol ARC_EMAC depends on OF_IRQ

- By depending on PHYLIB, we are causing a recursive dependency. PHYLIB
  only has a single dependency, "depends on NETDEVICES", which we are
  already depending on, so we can again hack our way into conformance by
  turning the PHYLIB dependency into a select.

drivers/of/Kconfig:69:error: recursive dependency detected!
drivers/of/Kconfig:69:  symbol OF_IRQ depends on IRQ_DOMAIN
kernel/irq/Kconfig:68:  symbol IRQ_DOMAIN is selected by REGMAP
drivers/base/regmap/Kconfig:7:  symbol REGMAP default is visible depending on REGMAP_MMIO
drivers/base/regmap/Kconfig:39: symbol REGMAP_MMIO is selected by MSCC_OCELOT_SWITCH_LIB
drivers/net/ethernet/mscc/Kconfig:15:   symbol MSCC_OCELOT_SWITCH_LIB is selected by MSCC_OCELOT_SWITCH
drivers/net/ethernet/mscc/Kconfig:22:   symbol MSCC_OCELOT_SWITCH depends on PHYLIB
drivers/net/phy/Kconfig:254:    symbol PHYLIB is selected by ARC_EMAC_CORE
drivers/net/ethernet/arc/Kconfig:19:    symbol ARC_EMAC_CORE is selected by ARC_EMAC
drivers/net/ethernet/arc/Kconfig:25:    symbol ARC_EMAC depends on OF_IRQ

Fixes: f4d0323b ("net: mscc: ocelot: convert MSCC_OCELOT_SWITCH into a library")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>