sunxi: f1c100s: Drop SYSRESET to enable reset functionality

The F1C100s DT contains the wrong compatible string for the watchdog,
which breaks reset functionality.
Updating the DT goes via the Linux tree, but to allow reset
functionality meanwhile (useful for development!), disable SYSRESET for
now, to let the old-fashioned watchdog driver kick in and provide the
reset_cpu() implementation.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>