Fix DXIL Debug Source debugging not activating in specific case

If the debug source information comes from the DXBC chunk then the source filename won't have had its path separator standarised and the filename matching won't work

renderdoc/driver/shaders/dxil/dxil_reflect.cpp

@@ -2091,7 +2091,8 @@ void Program::GetLineInfo(size_t instruction, uintptr_t offset, LineColumnInfo &
         RDCASSERT(!shaderFilePath.empty());
         for(int32_t iFile = 0; iFile < Files.count(); iFile++)
         {
-          rdcstr filePath = Files[iFile].filename;
+          // Files[] might come from DXIL or DXBC data : ensure the path separator is standardised in all cases
+          rdcstr filePath = standardise_directory_separator(Files[iFile].filename);
           if(filePath == shaderFilePath)
           {
             fileIndex = iFile;