Add a new option for and disable column number information as there
are no known current users of column info. Robustify and fix up
a few tests in the process. Reduces the size of debug information
by a small amount.

Part of PR14106

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@166236 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/debug-info-line3.c b/test/CodeGen/debug-info-line3.c
index a4e35e7..d01b023 100644
--- a/test/CodeGen/debug-info-line3.c
+++ b/test/CodeGen/debug-info-line3.c
@@ -12,5 +12,5 @@
   
 }
 
-// CHECK: ret void, !dbg !17
-// CHECK: !17 = metadata !{i32 6,
+// CHECK: ret void, !dbg [[LINE:.*]]
+// CHECK: [[LINE]] = metadata !{i32 6,