Fix infinite loop for structs in library function parameter

test/libsolidity/syntaxTests/structs/recursion/recursive_struct_nested_mapping_memory.sol

@@ -0,0 +1,10 @@
+library a {
+    struct b {
+        mapping (uint => b) c ;
+    }
+    // Segfaults in https://github.com/ethereum/solidity/issues/9443
+    function d(b memory) public {}
+}
+// ----
+// TypeError 4103: (149-157): Recursive structs can only be passed as storage pointers to libraries, not as memory objects to contract functions.
+// TypeError 4061: (149-157): Type struct a.b is only valid in storage because it contains a (nested) mapping.

test/libsolidity/syntaxTests/structs/recursion/recursive_struct_nested_mapping_storage.sol

@@ -0,0 +1,6 @@
+library a {
+    struct b {
+        mapping (uint => b) c ;
+    }
+    function d(b storage) public {}
+}