test-lib.sh: unfilter GIT_PERF_*

These variables are user parameters to control how to run the perf
tests. Allow users to do so.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/test-lib.sh b/t/test-lib.sh
index f50f834..bf4cf71 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -85,7 +85,7 @@
 		.*_TEST
 		PROVE
 		VALGRIND
-		PERF_AGGREGATING_LATER
+		PERF_
 	));
 	my @vars = grep(/^GIT_/ && !/^GIT_($ok)/o, @env);
 	print join("\n", @vars);