Remove tui_show_disassem_and_update_source

Remove tui_show_disassem_and_update_source

tui_show_disassem_and_update_source only has a single caller.  This
patch simplifies that caller, by having it call tui_show_disassem, and
then removes tui_show_disassem_and_update_source.

gdb/ChangeLog
2019-12-20  Tom Tromey  <tom@tromey.com>

	* tui/tui-winsource.c (tui_update_source_windows_with_addr): Call
	tui_show_disassem.
	* tui/tui-disasm.h (tui_show_disassem_and_update_source): Don't
	declare.
	* tui/tui-disasm.c (tui_show_disassem_and_update_source): Remove.

Change-Id: I7554eca8e259f3539ea7710f2ff369b4a630dd9d