clk: ti: Constify clkctrl_name

We can constify clkctrl_name in preparation for making use of the
clock-output-names property.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20220204071449.16762-2-tony@atomide.com


Signed-off-by: Stephen Boyd <sboyd@kernel.org>