patch 8.2.4241: some type casts are redundant

Problem:    Some type casts are redundant.
Solution:   Remove the type casts. (closes #9643)
diff --git a/src/window.c b/src/window.c
index 7425727..c77149f 100644
--- a/src/window.c
+++ b/src/window.c
@@ -6493,7 +6493,7 @@
 
 	    // clear the lines added to cmdline
 	    if (full_screen)
-		screen_fill((int)(cmdline_row), (int)Rows, 0,
+		screen_fill(cmdline_row, (int)Rows, 0,
 						   (int)Columns, ' ', ' ', 0);
 	    msg_row = cmdline_row;
 	    redraw_cmdline = TRUE;