Simplify tui_source_window_base::maybe_update method

tui_source_window_base::maybe_update takes a symtab_and_line, plus a
separate line number and PC.  Because a symtab_and_line already holds
a line number and a PC, it is possible to remove these extra
parameters.

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

	* tui/tui-winsource.h (struct tui_source_window_base)
	<maybe_update>: Remove line_no and addr parameters.
	* tui/tui-stack.c (tui_show_frame_info): Set PC on sal.  Update.
	* tui/tui-source.h (struct tui_source_window) <maybe_update>:
	Update.
	* tui/tui-source.c (tui_source_window::maybe_update): Remove
	line_no and addr parameters.
	* tui/tui-disasm.h (struct tui_disasm_window) <maybe_update>:
	Update.
	* tui/tui-disasm.c (tui_disasm_window::maybe_update): Remove
	line_no and addr parameters.

Change-Id: I33d8e1a669a179544edb4197f5f7c5429dfc368e