clocksource/drivers/timer-ti-dm: Fix warning for set but not used

We can get a warning for dmtimer_clocksource_init() with 'pa' set but
not used. This was used in the earlier revisions of the code but no
longer needed, so let's remove the unused pa and of_translate_address().
Let's also do it for dmtimer_clockevent_init() that has a similar issue.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200519155157.12804-1-tony@atomide.com