checker: fix or_block return &type mismatch (#7138)

vlib/v/checker/checker.v

@@ -1698,7 +1698,8 @@ pub fn (mut c Checker) check_or_expr(or_expr ast.OrExpr, ret_type table.Type, ex
 		match last_stmt {
 			ast.ExprStmt {
 				last_stmt_typ := c.expr(last_stmt.expr)
-				type_fits := c.check_types(last_stmt_typ, ret_type)
+				type_fits := c.check_types(last_stmt_typ, ret_type) && last_stmt_typ.nr_muls() ==
+					ret_type.nr_muls()
 				is_panic_or_exit := is_expr_panic_or_exit(last_stmt.expr)
 				if type_fits || is_panic_or_exit {
 					return

vlib/v/checker/tests/optional_or_block_mismatch.out

@@ -0,0 +1,7 @@
+vlib/v/checker/tests/optional_or_block_mismatch.vv:10:18: error: wrong return type `Bar` in the `or {}` block, expected `&Bar`
+    8 |
+    9 | fn main() {
+   10 |     x := foo() or { Bar{} }
+      |                     ~~~
+   11 |     println(x)
+   12 | }

vlib/v/checker/tests/optional_or_block_mismatch.vv

@@ -0,0 +1,12 @@
+module main
+
+struct Bar {}
+
+fn foo() ?&Bar {
+	return none
+}
+
+fn main() {
+	x := foo() or { Bar{} }
+	println(x)
+}