Use double instead of single quote to expand .

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@162830 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/scan-build/scan-build b/tools/scan-build/scan-build
index 3520826..0b7025b 100755
--- a/tools/scan-build/scan-build
+++ b/tools/scan-build/scan-build
@@ -1526,7 +1526,7 @@
 SetHtmlEnv(\@ARGV, $HtmlDir);
 if ($AnalyzeHeaders) { push @AnalysesToRun,"-analyzer-opt-analyze-headers"; }
 if ($AnalyzerStats) { push @AnalysesToRun, '-analyzer-checker=debug.Stats'; }
-if ($MaxLoop > 0) { push @AnalysesToRun, '-analyzer-max-loop $MaxLoop'; }
+if ($MaxLoop > 0) { push @AnalysesToRun, "-analyzer-max-loop $MaxLoop"; }
 
 # Delay setting up other environment variables in case we can do true
 # interposition.