msm: clock: Add a new API to print registers for debugging

clk_debug_print_hw() will format a list of register names and values, and
output the result to either the kernel log or a seq_file.

Change-Id: Ic225eb0261818faaee91b42955f2a517e927a30b
Signed-off-by: Patrick Daly <pdaly@codeaurora.org>