compiled into the kernel. This allows us to boot the same kernel on
machines with different master clock frequencies, so long as we can
determine the main clock frequency accurately. Cleanup the pmc clock
init function so it can be called in early boot so we can use the
serial port just after we call cninit.
# We have two calls to at91_pmc_clock_init for reasons unknown, that will
# be fixed later -- it is harmless for now.
