[PECOFF] Use the COFF subsystem field when determining the Triple.

Patch by walter erquinigo
Differential revision: https://reviews.llvm.org/D24284

llvm-svn: 282013
diff --git a/lldb/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.h b/lldb/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.h
index 2031382..b98c14c 100644
--- a/lldb/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.h
+++ b/lldb/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.h
@@ -128,6 +128,8 @@
 
   uint32_t GetPluginVersion() override;
 
+  bool IsWindowsSubsystem();
+
 protected:
   bool NeedsEndianSwap() const;