msm: clock: Allow registration of multiple MSM clock tables

If multiple clock drivers wish to use the framework in mach-msm/clock.c,
then it is necessary for additional clock tables to be registered after
msm_clock_init(). Add the msm_clock_register(table, size) API to
accomplish this. Unlike msm_clock_init(), msm_clock_register() can be
used multiple times and called after the kernel has finished booting.

To support debugfs features for clocks registered with the new API,
changes are required to debugfs initialization, which is now done as
part of msm_clock_init() rather than clock_late_init(). A linked list
is used to chain together the tables of clocks so their state can be
printed by clock_debug_print_enabled().

Change-Id: I9b480cd5d342701baef7da864c5b4d66969ec8ec
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>