sched: energy: calculate and update CPU capacity dynamically

One SoC can have multiple CPU speedbins which cannot be represented
with current energy model due to fixed capacity per CPU frequency
steps.

Provide CPU's all possible frequency steps instead of capacities along
with corresponding energy costs to be able to support different
speedbins.

Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
[markivx: Resolved merge-conflicts]
Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>

Change-Id: Ib865fd5ca7347946cfa532ca464dba4f9c51ced5
[satyap@codeaurora.org:
1. resolve trivial merge conflicts
2. port update_cpu_capacity function from msm-4.9 commit: 5e900d488428a6a
(ANDROID: arm64: Cpu invariant scheduler load-tracking and capacity support)
]
Signed-off-by: Satya Durga Srinivasu Prabhala <satyap@codeaurora.org>