msm: acpuclock: add frequency steps at lower cpu frequencies
with the previous commit "cpufreq: ondemand: Eliminate the dead band
effect", the required frequencies are selected more accurately depending
on the cpu load. With the increased accuracy of frequency selection,
increasing the number of available frequencies will help avoiding higher
than required frequencies. This patch refines the frequency steps to
54 MHz from 108 MHz for frequencies lower than 1080 MHz where the cpu
spends most of its time.

--mrg666