ARM: update subtarget information for Windows on ARM

Update the subtarget information for Windows on ARM.  This enables using the MC
layer to target Windows on ARM.

llvm-svn: 205459
diff --git a/llvm/lib/Target/ARM/ARMSubtarget.cpp b/llvm/lib/Target/ARM/ARMSubtarget.cpp
index d2f3b20..5222c1b 100644
--- a/llvm/lib/Target/ARM/ARMSubtarget.cpp
+++ b/llvm/lib/Target/ARM/ARMSubtarget.cpp
@@ -212,6 +212,12 @@
     }
   }
 
+  // FIXME: this is invalid for WindowsCE
+  if (isTargetWindows()) {
+    TargetABI = ARM_ABI_AAPCS;
+    NoARM = true;
+  }
+
   if (isAAPCS_ABI())
     stackAlignment = 8;
   if (isTargetNaCl())