Makefile: Fix dependencies for developerbox_spi

Note: This patch was backported from the master branch and it was
modified so that it can be applied on the 1.2.x branch.

The developerbox_spi programmer depends on bitbang SPI support. Thus,
fix that.

Signed-off-by: Felix Singer <felixsinger@posteo.net>
Change-Id: Ic0fe589ffdccede0fbf6360c2bebe58a36654f10
Reviewed-on: https://review.coreboot.org/c/flashrom/+/66096
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Thomas Heijligen <src@posteo.de>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/68064
1 file changed