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/zynq_cse_nand_defconfig b/configs/zynq_cse_nand_defconfig
index 7ca7483..74c35f3 100644
--- a/configs/zynq_cse_nand_defconfig
+++ b/configs/zynq_cse_nand_defconfig
@@ -78,5 +78,6 @@
 CONFIG_NAND_ZYNQ=y
 CONFIG_SYS_NAND_ONFI_DETECTION=y
 CONFIG_ARM_DCC=y
+CONFIG_SYS_TIMER_COUNTS_DOWN=y
 # CONFIG_GZIP is not set
 # CONFIG_LMB is not set