chore: print bitmap on FFA_NOTIFICATION_BIND

Add the notification bitmap to log error.

Signed-off-by: J-Alves <joao.alves@arm.com>
Change-Id: I2bfb746327736f814a5adce29745d5db0bbd6ea0
diff --git a/src/api.c b/src/api.c
index 70459d7..6e847e0 100644
--- a/src/api.c
+++ b/src/api.c
@@ -3795,7 +3795,8 @@
 	}
 
 	if (notifications == 0U) {
-		dlog_verbose("No notifications have been specified.\n");
+		dlog_verbose("No notifications have been specified %x.\n",
+			     notifications);
 		return ffa_error(FFA_INVALID_PARAMETERS);
 	}