Revert "ANDROID: sched: add em_cpu_energy vendor hook"

This reverts commit b5a8eefc as it
causes merge conflicts in 6.0-rc1.  If this is still needed after
6.0-rc1 is merged, it can be added back.

Bug: 178022444
Cc: Yun Hsiang <yun.hsiang@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I73d2cb0674bb2a6cab10dcec1dc1a151ebf05d8c