Prevent /link being passed twice in compiler flags

This does not work correctly with clang-cl/lld-link

Author: Frankie Robertson

mesonbuild/compilers/mixins/visualstudio.py

@@ -188,7 +188,7 @@ def get_optimization_args(self, optimization_level: str) -> T.List[str]:
         return args
 
     def linker_to_compiler_args(self, args: T.List[str]) -> T.List[str]:
-        return ['/link'] + args
+        return ['/link'] + [arg for arg in args if arg != "/link"]
 
     def get_pic_args(self) -> T.List[str]:
         return [] # PIC is handled by the loader on Windows