macros: fix select macro to process 64 branches (#4519)

Co-authored-by: DevSabb <devsabb@local>

tokio/src/macros/select.rs

@@ -801,6 +801,9 @@ macro_rules! count {
     (_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _) => {
         63
     };
+    (_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _) => {
+        64
+    };
 }
 
 #[macro_export]

tokio/tests/macros_select.rs

@@ -461,6 +461,7 @@ async fn many_branches() {
         x = async { 1 } => x,
         x = async { 1 } => x,
         x = async { 1 } => x,
+        x = async { 1 } => x,
     };
 
     assert_eq!(1, num);