gdb/tui: Remove casts of NULL during assignment.

In the following code:

    struct symbol *wsym = (struct symbol *) NULL;

the cast of NULL is redundant, it adds noise, and is just one more thing
to change if the type of wsym ever changes.  There are a relatively
small number of places in gdb where the above code pattern is used.
Usually the cast is removed like this:

    struct symbol *wsym = NULL;

This commit updates all the places within the gdb/tui directory where we
cast NULL during assignment, removing the cast.

gdb/ChangeLog:

	* tui/tui-data.c (win_with_focus): Remove cast of NULL pointer.
	(tui_next_win): Likewise.
	(tui_prev_win): Likewise.
	(tui_partial_win_by_name): Likewise.
	(tui_init_generic_part): Likewise.
	(init_content_element): Likewise.
	(tui_del_window): Likewise.
	(tui_free_window): Likewise.
	(tui_del_data_windows): Likewise.
	(tui_free_data_content): Likewise.
	* tui/tui-layout.c (make_source_or_disasm_window): Likewise.
	* tui/tui-regs.c (tui_show_register_group): Likewise.
	* tui/tui-win.c (tui_resize_all): Likewise.
	(tui_set_focus): Likewise.
	(tui_set_win_height): Likewise.
	(make_invisible_and_set_new_height): Likewise.
	* tui/tui-windata.c (tui_delete_data_content_windows): Likewise.
	* tui/tui-wingeneral.c (make_visible): Likewise.

1 files changed, 1 insertions, 1 deletions

diff --git a/gdb/tui/tui-wingeneral.c b/gdb/tui/tui-wingeneral.c
index b95da49..b6d3d0f 100644
--- a/gdb/tui/tui-wingeneral.c
+++ b/gdb/tui/tui-wingeneral.c
@@ -194,7 +194,7 @@ make_visible (struct tui_gen_win_info *win_info, int visible)
     {
       win_info->is_visible = FALSE;
       tui_delete_win (win_info->handle);
-      win_info->handle = (WINDOW *) NULL;
+      win_info->handle = NULL;
     }
 
   return;