error log: clarify for using more resources than reserved

Figure out how many resources were reserved, how many of those match the
requirements, and how many are used, and log one of three matching error
messages for that situation.

For that purpose, allow find()ing reserved resources without logging anything,
using a log_label=None arg.

Change-Id: I1c67600ba69351859e46b8b2f368ee8106db0993
1 file changed