fixes for interactive governor codeaurora msm-3.7

====================
cpufreq: fix interactive bug during hotplug

When a new cpu is added and if does not enter idle
for long, the interactive timer is not started and hence
the cpu remains at lowest frequecny, despite the system
load. This impacts mainly benchmarks. Starting a timer
at governor start to handle low frequency.

Change-Id: I8ac9705b9f166a95715c985efacd2ae8ef387cb7
Signed-off-by: Narayanan Gopalakrishnan <nargop@codeaurora.org>

======================
cpufreq: interactive: Fix blocked task warnings

Running a kernel that never enables the interactive cpufreq
will eventually hit the following warning:

INFO: task kinteractiveup:112 blocked for more than 120 seconds.
kinteractiveup  D c07ae3a4  7072   112      2 0x00000000
[<c07ae3a4>] (__schedule+0x4e4/0x5c4) from [<c00a1b8c>] (kthread+0x70/0x94)
[<c00a1b8c>] (kthread+0x70/0x94) from [<c000f368>]
(kernel_thread_exit+0x0/0x8)

due to the fact that the kthread is never woken up after being
forked. Kick the thread to its idle loop so that it can
schedule() and move out of the D state.

Change-Id: Idc490e707d9a14dd143306a8ee1c2241320d29d5
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>