omap3: Decrease cpufreq transition latency

Adjust OMAP3 frequency transition latency from 10,000,000uS to a more
reasonable 300,000uS.  This causes ondemand and conservative governors to
sample CPU load more often resulting in more responsive behavior.

Tested on Android 2.6.29; using this value and conservative governor, CORE
power consumption on Zoom2 was comparable to the old and unresponsive
10,000,000uS value while UI responsiveness was greatly improved.

Signed-off-by: Mike Turquette <mturquette@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>