payloads/Kconfig: Put option *None* at the top

As *None* is special and not a payload, it makes sense to put it at the
top. Also, it was at before the latest addition of the FIT payload
choice.

Fixes: a892cde6 (lib: Add FIT payload support)
Change-Id: I52163ea9472308ecbc396012d9912b9617e0c318
Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reviewed-on: https://review.coreboot.org/27414
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
1 file changed