cpufreq.c: add userspace voltage control. Original implementation from faux123 (which was based on Michael Huang's OMAP4460 work). Interface cleaned up, made more robust and secure

Conflicts:
	drivers/cpufreq/cpufreq.c
cpufreq: fix wrong report of the frequency table in the UV interface.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
tegra: includes fixup.