rtc: pl031: document struct pl031_vendor_data members

Document the range related members of struct pl031_vendor_data.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202503011015.SYvdddTc-lkp@intel.com/
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20250305221659.1153495-1-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Author: alexandrebelloni

drivers/rtc/rtc-pl031.c

@@ -74,6 +74,8 @@
  * @st_weekday: if this is an ST Microelectronics silicon version that need
  *	the weekday fix
  * @irqflags: special IRQ flags per variant
+ * @range_min: minimum date/time supported by the RTC
+ * @range_max: maximum date/time supported by the RTC
  */
 struct pl031_vendor_data {
 	struct rtc_class_ops ops;