net: dsa: ocelot: fix selecting MFD_OCELOT

Commit 3d7316ac ("net: dsa: ocelot: add external ocelot switch
control") adds config NET_DSA_MSCC_OCELOT_EXT, which selects the
non-existing config MFD_OCELOT_CORE.

Replace this select with the intended and existing MFD_OCELOT.
Signed-off-by: NLukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: NColin Foster <colin.foster@in-advantage.com>
Link: https://lore.kernel.org/r/20230215104631.31568-1-lukas.bulwahn@gmail.comSigned-off-by: NPaolo Abeni <pabeni@redhat.com>

drivers/net/dsa/ocelot/Kconfig

@@ -14,7 +14,7 @@ config NET_DSA_MSCC_OCELOT_EXT
 	depends on NET_VENDOR_MICROSEMI
 	depends on PTP_1588_CLOCK_OPTIONAL
 	select MDIO_MSCC_MIIM
-	select MFD_OCELOT_CORE
+	select MFD_OCELOT
 	select MSCC_OCELOT_SWITCH_LIB
 	select NET_DSA_MSCC_FELIX_DSA_LIB
 	select NET_DSA_TAG_OCELOT_8021Q