ANDROID: cpufreq: times: Remove /proc/uid_concurrent_{active,policy}_time

This removes the portion of commit 4242998e ("ANDROID: cpufreq:
times: add /proc/uid_concurrent_{active,policy}_time") adding new
files for per-UID stats while preserving a change to skip accounting
for idle tasks.

Bug: 127641090
Signed-off-by: Connor O'Brien <connoro@google.com>
Change-Id: I1e334dcc71201118aa62115fa5247263e545e8d6