rtc: Add fallbacks for dm functions

This adds fallbacks for the various dm_rtc_* functions. This allows
common code to use these functions without ifdefs.

Fixes: c8ce7ba87d1 ("misc: Add support for nvmem cells")
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
1 file changed