msm: acpuclock-krait: Update 'unknown rate' debug prints to warnings

While not fatal, boot performance will be suboptimal if the L2 or
CPU frequencies at boot are not in the frequency tables. This is
because acpuclock 'plays it safe' by applying the lowest possible
clock rate in such situations to ensure clocks are not set higher
than boot-up voltages can support.

Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>