patch 9.0.0904: various comment and indent flaws

Problem:    Various comment and indent flaws.
Solution:   Improve comments and indenting.
diff --git a/src/message.c b/src/message.c
index d90666f..a60d330 100644
--- a/src/message.c
+++ b/src/message.c
@@ -1311,9 +1311,8 @@
 					|| c == K_X2MOUSE))
 				);
 	ui_breakcheck();
-	/*
-	 * Avoid that the mouse-up event causes visual mode to start.
-	 */
+
+	// Avoid that the mouse-up event causes Visual mode to start.
 	if (c == K_LEFTMOUSE || c == K_MIDDLEMOUSE || c == K_RIGHTMOUSE
 					  || c == K_X1MOUSE || c == K_X2MOUSE)
 	    (void)jump_to_mouse(MOUSE_SETPOS, NULL, 0);