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_qspi_defconfig b/configs/zynq_cse_qspi_defconfig
index 215d5ed..c623caf 100644
--- a/configs/zynq_cse_qspi_defconfig
+++ b/configs/zynq_cse_qspi_defconfig
@@ -90,5 +90,6 @@
 # CONFIG_SPI_FLASH_USE_4K_SECTORS is not set
 CONFIG_ARM_DCC=y
 CONFIG_ZYNQ_QSPI=y
+CONFIG_SYS_TIMER_COUNTS_DOWN=y
 # CONFIG_GZIP is not set
 # CONFIG_LMB is not set