spi: Propagate default fwnode to the SPI controller device

spi: Propagate default fwnode to the SPI controller device

Most of the SPI controller drivers share the parent's fwnode
by explicit assignment. Propagate the default by SPI core,
so they may drop that in the code. Only corner cases may require
a special treatment and we simply (re)assign the controller's
fwnode explicitly (as it's done right now, no changes required
for that).

Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Tested-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20260112203534.4186261-2-andriy.shevchenko@linux.intel.com
Reviewed-by: Linus Walleij <linusw@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>