msm: acpuclock-krait: Discard unused SoC-specific data by using __initdata

Refactor the initialization code so that datastructures that must be
kept are kmemduped and the rest are discarded after the kernel has
booted with the help of __initdata markings.

For a typically-compiled all-in-one kernel containing support for
msm8960, apq8064, msm8627 and msm8930, this allows 11.5K to be moved
from the .data to the .init.data section, with less than 10% of that
retained in dynamically-allocated memory (the exact amount varies
depending on the device the kernel is booted on).

Change-Id: I505eef8f10dc0e44bab15954b797252c3c408e50
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>