clk: qcom: clk-cpu-qcs405: Reorg the CPU clock code

As the APCS cmd & pll is using the same regmap config to register with
regmap framework it fails to create the debugfs directory. Associate a name
with the regmap config for each. While at it get the regulator handles
from DT before doing a regmap. Also clean up the rcu_read_lock/unlock as
they are not required.

Change-Id: I54cad03a4c5e22a0739ca73fb3a0a908197401f9
Signed-off-by: Taniya Das <tdas@codeaurora.org>