clk: ti: drop locking code from mux/divider drivers

TI's mux and divider clock drivers do not require locking and they do
not initialize internal spinlocks. This code was occasionally
copy-posted from generic mux/divider drivers. So remove it.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>