clocksource/drivers/timer-microchip-pit64b: Drop obsolete dependency on COMPILE_TEST

Since commit 0166dc11 ("of: make CONFIG_OF user selectable"), it
is possible to test-build any driver which depends on OF on any
architecture by explicitly selecting OF. Therefore depending on
COMPILE_TEST as an alternative is no longer needed.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Claudiu Beznea <claudiu.beznea@microchip.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20230121182911.4e47a5ff@endymion.delvare


Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>