perf: Remove BEAC registers from LLCC PMU

These are no longer required for the proper functioning of the PMU, so they
can be removed. Update the scaling factor, which we previously set, to the
default value to reflect this.

Change-Id: Iaf6800277f51478bc6fa2699cbd218bbb7a8f974
Signed-off-by: Jonathan Avila <avilaj@codeaurora.org>