cpufreq: interactive: change io_is_busy handling a bit

Use get_cpu_idle_time_jiffy and get_cpu_idle_time.
Change default to true.

Change-Id: I163feb8c5dcd5961bdd529a06b85312b7eba7e9e
Signed-off-by: Blechd0se <alex.christ@hotmail.de>
block: various I/O-Tweaks

Change some default values of our schedulers.

Deadline should now perform more like FiFo.
Change vm_readahead to 512.

Change-Id: If16227f534362c0e506a3d920c574fb5b1d06e4f
Signed-off-by: Blechd0se <alex.christ@hotmail.de>