Remove FileSystem::MakeDirectory.

Have callers use llvm::sys::fs::create_directory() instead.

Differential Revision: https://reviews.llvm.org/D31086

llvm-svn: 298203
diff --git a/lldb/source/Target/Platform.cpp b/lldb/source/Target/Platform.cpp
index 95182e1..d3f265d 100644
--- a/lldb/source/Target/Platform.cpp
+++ b/lldb/source/Target/Platform.cpp
@@ -761,7 +761,7 @@
 
 Error Platform::MakeDirectory(const FileSpec &file_spec, uint32_t permissions) {
   if (IsHost())
-    return FileSystem::MakeDirectory(file_spec, permissions);
+    return llvm::sys::fs::create_directory(file_spec.GetPath(), permissions);
   else {
     Error error;
     error.SetErrorStringWithFormat("remote platform %s doesn't support %s",