[AVR] Cherry-pick LLVM patch (D68524) "Rewrite the function calling convention"

dylanmckay · dylanmckay · commit 95a385d4b6ff · 2019-11-28T01:19:53.000+13:00
This fixes #92. At the time of cherry-picking, this patch has not yet been upstreamed.
diff --git a/src/llvm-project b/src/llvm-project
@@ -1 +1 @@
-Subproject commit 4350776601bc671e6e055bfbe32add34b70d2635
+Subproject commit 38a608b66ce1a8c45b4975726e7f869a5f1cc60a
