If the RTC module is compiled as a module, the hctosys fails to
initialize because ds1307 is loaded later.
Fixes:
[ 2.004145] hctosys: unable to open rtc device (rtc0)
[ 11.957997] rtc-ds1307 0-006f: registered as rtc0
This is similar to commit 5481ce9a1157a43d8b2c963e03fb243e70974361,
which was done for imx6 target.
Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>
(cherry picked from commit dc7f78da97c62cd6c17a75f754da5bf6b957837d)
4130e7ed54