Convert CONFIG_CLOCKS to Kconfig

This converts the following to Kconfig:
   CONFIG_CLOCKS

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/zynq_cse_nor_defconfig b/configs/zynq_cse_nor_defconfig
index 4e8661b..1d55d99 100644
--- a/configs/zynq_cse_nor_defconfig
+++ b/configs/zynq_cse_nor_defconfig
@@ -20,6 +20,7 @@
 CONFIG_USE_PREBOOT=y
 # CONFIG_DISPLAY_CPUINFO is not set
 # CONFIG_BOARD_LATE_INIT is not set
+CONFIG_CLOCKS=y
 CONFIG_SPL_STACK_R=y
 # CONFIG_CMDLINE_EDITING is not set
 # CONFIG_AUTO_COMPLETE is not set