cpufreq: interactive: fix NULL pointer dereference at sysfs ops

sysfs ops for target_loads and above_hispeed_delay can be called before
initializing tunables at CPUFREQ_GOV_POLICY_INIT. Create sysfs entries after
initialization.

Change-Id: I50356198d7629731c0d32a3066d61fe8354e0001
Signed-off-by: Minsung Kim <ms925.kim@samsung.com>
Git-commit: 0ac276ebfca1d405153f4a3476aa1f7f66bbbec8
Git-Repo: https://android.googlesource.com/kernel/common.git


[junjiew@codeaurora.org: Resolve merge conflicts]
Signed-off-by: Junjie Wu <junjiew@codeaurora.org>