Revert "Enable eco mode based on eco_mode=0/1 in cmdline"

This reverts commit 1c19d630a82f69c195086924a79dcc8ce96ee892.

Change-Id: Ie0887e7af2b7731d5f5a7ebdf67446072e29e8c3
Merge "Revert "Enable eco mode based on eco_mode=0/1 in cmdline"" into kitkat