linkers: Split Visual Studio Linker into a mixin

Because ICL has it's own linker that behaves basically just like the
VisualStudioLinker, but with a few peices of extra functionality.

mesonbuild/linkers.py

@@ -23,7 +23,7 @@ class StaticLinker:
         return mesonlib.is_windows()
 
 
-class VisualStudioLinker(StaticLinker):
+class VisualStudioLikeLinker:
     always_args = ['/NOLOGO']
 
     def __init__(self, exelist, machine):
@@ -31,7 +31,7 @@ class VisualStudioLinker(StaticLinker):
         self.machine = machine
 
     def get_exelist(self):
-        return self.exelist[:]
+        return self.exelist.copy()
 
     def get_std_link_args(self):
         return []
@@ -50,10 +50,10 @@ class VisualStudioLinker(StaticLinker):
         return []
 
     def get_always_args(self):
-        return VisualStudioLinker.always_args[:]
+        return self.always_args.copy()
 
     def get_linker_always_args(self):
-        return VisualStudioLinker.always_args[:]
+        return self.always_args.copy()
 
     def build_rpath_args(self, build_dir, from_dir, rpath_paths, build_rpath, install_rpath):
         return []
@@ -77,6 +77,11 @@ class VisualStudioLinker(StaticLinker):
         return []
 
 
+class VisualStudioLinker(VisualStudioLikeLinker, StaticLinker):
+
+    """Microsoft's lib static linker."""
+
+
 class ArLinker(StaticLinker):
 
     def __init__(self, exelist):