The 'l' length modifier makes sense with the scanlist conversion specifier.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@148586 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/FormatString.cpp b/lib/Analysis/FormatString.cpp
index 207f773..fb52742 100644
--- a/lib/Analysis/FormatString.cpp
+++ b/lib/Analysis/FormatString.cpp
@@ -531,6 +531,7 @@
         case ConversionSpecifier::nArg:
         case ConversionSpecifier::cArg:
         case ConversionSpecifier::sArg:
+        case ConversionSpecifier::ScanListArg:
           return true;
         default:
           return false;