cpufreq: Introduce new relation for freq selection

Introduce CPUFREQ_RELATION_C for frequency selection.
It selects the frequency with the minimum euclidean distance to target.
In case of equal distance between 2 frequencies, it will select the
greater frequency.

Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[zwliew: Backport to Linux 3.4]
Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>

Conflicts:
	drivers/cpufreq/freq_table.c
	include/linux/cpufreq.h
cpufreq: interactive: Choose frequency closest to target

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

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