net: dsa: mv88e6xxx: Remove bogus Kconfig dependency.

The mv88e6xxx is a DSA driver, and it implements DSA style time
stamping of PTP frames.  It has no need of the expensive option to
enable PHY time stamping.  Remove the bogus dependency.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Brandon Streiff <brandon.streiff@ni.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/dsa/mv88e6xxx/Kconfig

@@ -25,7 +25,6 @@ config NET_DSA_MV88E6XXX_PTP
 	default n
 	depends on NET_DSA_MV88E6XXX_GLOBAL2
 	depends on PTP_1588_CLOCK
-	imply NETWORK_PHY_TIMESTAMPING
 	help
 	  Say Y to enable PTP hardware timestamping on Marvell 88E6xxx switch
 	  chips that support it.