Change raw_fd_ostream to take flags as an optional bitmask

instead of as two bools.  Use this to add a F_Append flag
which has the obvious behavior.

Other unrelated changes conflated into this patch:

1. REmove EH stuff from llvm-dis and llvm-as, the try blocks
   are dead.
2. Simplify the filename inference code in llvm-as/llvm-dis,
   because raw_fd_ostream does the right thing with '-'.
3. Switch machine verifier to use raw_ostream instead of ostream
   (Which is the thing that needed append in the first place).




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79807 91177308-0d34-0410-b5e6-96231b3b80d8

tools/lto/LTOCodeGenerator.cpp

@@ -178,9 +178,8 @@ const void* LTOCodeGenerator::compile(size_t* length, std::string& errMsg)
     // generate assembly code
     bool genResult = false;
     {
-      raw_fd_ostream asmFD(uniqueAsmPath.c_str(),
-                           /*Binary=*/false, /*Force=*/true,
-                           errMsg);
+      raw_fd_ostream asmFD(uniqueAsmPath.c_str(), errMsg,
+                           raw_fd_ostream::F_Force);
       formatted_raw_ostream asmFile(asmFD);
       if (!errMsg.empty())
         return NULL;