Revert "net: micrel: fix KS8851_MLL Kconfig"

This reverts commit 05b4c37fca84976ab9e3873d36fe53cd88d45408 which is
commit c3efcedd272aa6dd5929e20cf902a52ddaa1197a upstream.

The upstream commit c3efcedd272a ("net: micrel: fix KS8851_MLL Kconfig")
depends on e5f31552674e ("ethernet: fix PTP_1588_CLOCK dependencies")
which is not part of Linux 4.19.y . Revert the aforementioned commit to
prevent breakage in 4.19.y .

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Sasha Levin <sashal@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/net/ethernet/micrel/Kconfig b/drivers/net/ethernet/micrel/Kconfig
index aa12bac..b7e2f49 100644
--- a/drivers/net/ethernet/micrel/Kconfig
+++ b/drivers/net/ethernet/micrel/Kconfig
@@ -45,7 +45,6 @@
 config KS8851_MLL
 	tristate "Micrel KS8851 MLL"
 	depends on HAS_IOMEM
-	depends on PTP_1588_CLOCK_OPTIONAL
 	select MII
 	---help---
 	  This platform driver is for Micrel KS8851 Address/data bus