cpufreq: interactive Allow arbitrary speed / timer mappings

* Moved commit https://github.com/zwliew/ghost/commit/d41afc2e34effec7c0c4a27e2bea47552d3f4e6e to round_nw_to_start().

Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>
ramdisk: Re-configure interactive governor

Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>