LU-7329 tests: increase sanity test_60b llog_test line count

LU-7329 tests: increase sanity test_60b llog_test line count

With the increased number of tests in sanity test_60a due to the
landing of LU-6556, LU-6714, and LU-7329, the check test_60b that
detects CWARN/CERROR() rate limiting can be exceeded in some cases,
up to 81 llog_test lines in my testing.

Increase the maximum line count correspondingly.

Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Change-Id: I08e899f0faed10430aae0d90a54f43aad7500c1e
Reviewed-on: http://review.whamcloud.com/17670
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Faccini Bruno <bruno.faccini@intel.com>
Reviewed-by: James Nunez <james.a.nunez@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>