rtc: fsl-ftm-alarm: add MODULE_TABLE()

The module doesn't load automatically. Fix it by adding the missing
MODULE_TABLE().

Fixes: 7b0b551d ("rtc: fsl-ftm-alarm: add FTM alarm driver")
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210414084006.17933-1-michael@walle.cc