rtc: rx8025: Fix a parameter to %ptR in rx8025_read_alarm()

The commit 1921cab1 ("rtc: rx8025: Switch to use %ptR") converted
the driver to use new %p extension, but actually used wrong type of
the parameter in one case.

Fix a parameter to %ptR in rx8025_read_alarm().

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>