remove nowhere used symbol CONFIG_SYS_CLKS_IN_HZ

Basically finish what the following commit started a long time ago:

488f5d8790c451fc527fe5d2ef218f2a5e40ea17

Signed-off-by: Marcel Ziswiler <marcel@ziswiler.com>

For mx35pdk/woodburn:

Acked-by: Stefano Babic <sbabic@denx.de>
12 files changed