msm: pm2: Remove unnecessary checks in arch_idle & msm_pm_enter

Currently default power mode for idle & suspend paths are passed
as a module parameter. It can be tweaked at run time to switch to
a different power mode.

These parameters are not necessary because driver structure has
already fields like "idle_enable", "idle_supported", "suspend_enable"
and "suspend_supported". These parameters can be changed via sysfs
entries and enable only the user interested modes.

Change-Id: I80d925f35323accb805f8895f90c52bcbfc9143e
Signed-off-by: Murali Nalajala <mnalajal@codeaurora.org>