net: fec: forbid FEC_PTP on SoCs that do not support

Beside imx6q, the kernel built from imx_v6_v7_defconfig is also
supposed to be running on other IMX SoCs that do not have the PTP
block.  Before fec driver gets fixed to run-time detect target hardware
rather than conditional compiling with #ifdef CONFIG_FEC_PTP, let's
give it a quick fix in Kconfig to forbid FEC_PTP on those IMX SoCs that
do not support PTP.
Reported-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/freescale/Kconfig

@@ -94,9 +94,8 @@ config GIANFAR
 
 config FEC_PTP
 	bool "PTP Hardware Clock (PHC)"
-	depends on FEC && ARCH_MXC
+	depends on FEC && ARCH_MXC && !SOC_IMX25 && !SOC_IMX27 && !SOC_IMX35 && !SOC_IMX5
 	select PTP_1588_CLOCK
-	default y if SOC_IMX6Q
 	--help---
 	  Say Y here if you want to use PTP Hardware Clock (PHC) in the
 	  driver.  Only the basic clock operations have been implemented.