power: qcom: Select CPU_IDLE_MULTIPLE_DRIVERS

CPU_IDLE_MULTIPLE_DRIVERS config option allows the cpuidle
framework to use different drivers for each CPU. This is
useful if the system is having different CPU latencies and
states. Enable CPU_IDLE_MULTIPLE_DRIVERS config to support
multiple cpu idle drvier and fix compilation errors.

Change-Id: Ibb35dbb1fb48025a411b81f5238f3a016c38dc5c
Signed-off-by: Murali Nalajala <mnalajal@codeaurora.org>