bisect-runner.pl should check for t/perl when building test_prep.

Checking for perl doesn't spot the cases where make aborts after perl is
built but before test_prep is completed.

diff --git a/Porting/bisect-runner.pl b/Porting/bisect-runner.pl
index 57e1d91..a27f44c 100755 (executable)
--- a/Porting/bisect-runner.pl
+++ b/Porting/bisect-runner.pl
@@ -720,7 +720,7 @@ if ($target ne 'miniperl') {
     system "make $j $target";
 }
 
-my $expected = $target =~ /^test/ ? 'perl' : $target;
+my $expected = $target =~ /^test/ ? 't/perl' : $target;
 my $missing_target = $expected =~ /perl$/ ? !-x $expected : !-r $expected;
 
 if ($options{'test-build'}) {