clk: tl1: add dsu clock notify [1/1]

clk: tl1: add dsu clock notify [1/1]

PD#SWPL-2842

Problem:
when set dsu clock, it will hang up

Solution:
1.add dsu clock notify, when set rate of
dsu_fixed_sel0 clock, dsu parent should switch to
dsu_fixed_sel1 to avoid hang up.

Verify:
verify on t962x2_x301

Change-Id: I55e7a61cfb12b973f423312892700f2d08e75cbd
Signed-off-by: Jian Hu <jian.hu@amlogic.com>