layerscape: armv8_64b: enable Microsemi phy driver for FRWY-LS1046A

Enable the Microsemi phy driver to support the VSC8514 QSGMII phy on the
FRWY-LS1046A board.

Otherwise, the "Generic PHY" driver is used.

Signed-off-by: Martin Schiller <ms@dev.tdt.de>

target/linux/layerscape/armv8_64b/config-5.4

@@ -502,6 +502,7 @@ CONFIG_MFD_CORE=y
 CONFIG_MFD_SYSCON=y
 # CONFIG_MFD_VEXPRESS_SYSREG is not set
 CONFIG_MICREL_PHY=y
+CONFIG_MICROSEMI_PHY=y
 CONFIG_MIGRATION=y
 CONFIG_MMC=y
 CONFIG_MMC_BLOCK=y