parser: multiple names error

vlib/v/checker/tests/multi_names_err.out

@@ -0,0 +1,5 @@
+vlib/v/checker/tests/multi_names_err.v:2:4: error: unexpected name `a`
+    1 | fn main() {
+    2 |     a a a a := 1
+      |       ^
+    3 | }

vlib/v/checker/tests/multi_names_err.vv

@@ -0,0 +1,3 @@
+fn main() {
+	a a a a := 1
+}

vlib/v/parser/parser.v

@@ -472,6 +472,8 @@ pub fn (mut p Parser) stmt() ast.Stmt {
 				return ast.GotoLabel{
 					name: name
 				}
+			} else if p.tok.kind == .name && p.peek_tok.kind == .name {
+				p.error_with_pos('unexpected name `$p.peek_tok.lit`', p.peek_tok.position())
 			}
 			epos := p.tok.position()
 			expr := p.expr(0)