phy: ti: Fix compilation failures without REGMAP

This driver requires regmap or the compile fails:

drivers/phy/ti/phy-gmii-sel.c:43:27: error: array type has incomplete element type ‘struct reg_field’
  const struct reg_field (*regfields)[PHY_GMII_SEL_LAST];

Add it to kconfig.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/phy/ti/Kconfig

@@ -82,6 +82,7 @@ config PHY_TI_GMII_SEL
 	default y if TI_CPSW=y
 	depends on TI_CPSW || COMPILE_TEST
 	select GENERIC_PHY
+	select REGMAP
 	default m
 	help
 	  This driver supports configuring of the TI CPSW Port mode depending on