Convert CONFIG_SYS_TIMER_COUNTS_DOWN to Kconfig

This converts the following to Kconfig:
   CONFIG_SYS_TIMER_COUNTS_DOWN

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/socfpga_vining_fpga_defconfig b/configs/socfpga_vining_fpga_defconfig
index 96c0ebb..cdad36b 100644
--- a/configs/socfpga_vining_fpga_defconfig
+++ b/configs/socfpga_vining_fpga_defconfig
@@ -116,3 +116,4 @@
 CONFIG_USB_GADGET_DOWNLOAD=y
 CONFIG_DESIGNWARE_WATCHDOG=y
 CONFIG_WDT=y
+CONFIG_SYS_TIMER_COUNTS_DOWN=y