deferred: Add @phan-mandatory-param for function name arguments

Providing the function name is often optional from the php code,
but it is needed for better logging, so make it mandatory and let phan
report issues about this.

Bug: T374546
Follow-Up: I5227f2fa65850ac8c6f620900f22d1f4e7bfd470
Change-Id: I3becd23d3ba9f452a8afd833d509cd907e56ca47

includes/deferred/MWCallableUpdate.php

@@ -25,7 +25,7 @@ class MWCallableUpdate
 	 * @param callable $callback One of the following:
 	 *    - A Closure callback that takes the caller name as its argument
 	 *    - A non-Closure callback that takes no arguments
-	 * @param string $fname Calling method
+	 * @param string $fname Calling method @phan-mandatory-param
 	 * @param IDatabase|IDatabase[] $dependeeDbws DB handles which might have pending writes
 	 *  upon which this update depends. If any of the handles already has an open transaction,
 	 *  a rollback thereof will cause this update to be cancelled (if it has not already run).

includes/deferred/TransactionRoundDefiningUpdate.php

@@ -19,7 +19,7 @@ class TransactionRoundDefiningUpdate
 
 	/**
 	 * @param callable $callback
-	 * @param string $fname Calling method
+	 * @param string $fname Calling method @phan-mandatory-param
 	 */
 	public function __construct( callable $callback, $fname = ISQLPlatform::CALLER_UNKNOWN ) {
 		$this->callback = $callback;