filesystem: use std for CreateFolder

Remove custom platform implementation of `CreateFolder` and replace uses
with `std::filesystem::create_directories` which creates paths
recursively.

src/xenia/gpu/d3d12/pipeline_cache.cc

@@ -202,7 +202,7 @@ void PipelineCache::InitializeShaderStorage(
   // cost - though D3D's internal validation would possibly be enough to ensure
   // they are up to date).
   auto shader_storage_shareable_root = shader_storage_root / "shareable";
-  if (!xe::filesystem::CreateFolder(shader_storage_shareable_root)) {
+  if (!std::filesystem::create_directories(shader_storage_shareable_root)) {
     return;
   }
 

src/xenia/gpu/shader.cc

@@ -47,7 +47,7 @@ std::pair<std::filesystem::path, std::filesystem::path> Shader::Dump(
   auto target_path = base_path;
   if (!target_path.empty()) {
     target_path = std::filesystem::absolute(target_path);
-    xe::filesystem::CreateFolder(target_path);
+    std::filesystem::create_directories(target_path);
   }
 
   auto base_name =

src/xenia/gpu/trace_writer.cc

@@ -33,7 +33,7 @@ bool TraceWriter::Open(const std::filesystem::path& path, uint32_t title_id) {
   auto canonical_path = std::filesystem::absolute(path);
   if (canonical_path.has_parent_path()) {
     auto base_path = canonical_path.parent_path();
-    xe::filesystem::CreateFolder(base_path);
+    std::filesystem::create_directories(base_path);
   }
 
   file_ = xe::filesystem::OpenFile(canonical_path, "wb");