Fix a major regression on COFF targets introduced by r103267: 'discardable' section means that it is used only during the program load and can be discarded afterwards.
This way *only* debug sections can be discarded, but not the opposite. Seems like the copy-and-pasto from ELF code, since there it contains the reverse flag ('alloc').

llvm-svn: 107658
diff --git a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index 350d50c..a80cfc4 100644
--- a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -936,7 +936,7 @@
 getCOFFSectionFlags(SectionKind K) {
   unsigned Flags = 0;
 
-  if (!K.isMetadata())
+  if (K.isMetadata())
     Flags |=
       COFF::IMAGE_SCN_MEM_DISCARDABLE;
   else if (K.isText())