pch_gbe, ptp_pch: Fix the dependency direction between these drivers

In commit a24006ed ('ptp: Enable clock
drivers along with associated net/PHY drivers') I wrongly made
PTP_1588_CLOCK_PCH depend on PCH_GBE.  The dependency is really the
other way around.  Therefore make PCH_GBE select PTP_1588_CLOCK_PCH
and remove the 'default y' from the latter.
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/oki-semi/pch_gbe/Kconfig

@@ -7,6 +7,7 @@ config PCH_GBE
 	depends on PCI
 	select NET_CORE
 	select MII
+	select PTP_1588_CLOCK_PCH
 	---help---
 	  This is a gigabit ethernet driver for EG20T PCH.
 	  EG20T PCH is the platform controller hub that is used in Intel's

drivers/ptp/Kconfig

@@ -72,9 +72,7 @@ config DP83640_PHY
 
 config PTP_1588_CLOCK_PCH
 	tristate "Intel PCH EG20T as PTP clock"
-	depends on PCH_GBE
 	select PTP_1588_CLOCK
-	default y
 	help
 	  This driver adds support for using the PCH EG20T as a PTP
 	  clock. The hardware supports time stamping of PTP packets