Use isOSBinFormatMachO() instead of comparing the object format
against an enum.

llvm-svn: 223422
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index d70be30..067c389 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -772,8 +772,7 @@
     // The backend is hardwired to assume AAPCS for M-class processors, ensure
     // the frontend matches that.
     if (Triple.getEnvironment() == llvm::Triple::EABI ||
-        (Triple.getOS() == llvm::Triple::UnknownOS &&
-         Triple.getObjectFormat() == llvm::Triple::MachO) ||
+        Triple.getOS() == llvm::Triple::UnknownOS ||
         StringRef(CPUName).startswith("cortex-m")) {
       ABIName = "aapcs";
     } else {