clean up the coreboot submodules

also bring the coreboot/next modules in line with
the recent merge that did away with coreboot/dell7

the submodules for coreboot/haswell were still there,
and have now been deleted; the haswell tree was used
for the NRI patches, which were moved to /default some
time ago

Signed-off-by: Leah Rowe <leah@libreboot.org>

config/submodule/coreboot/next/fsp/module.cfg

@@ -0,0 +1,3 @@
+subrepo="https://review.coreboot.org/fsp.git"
+subrepo_bkup="https://github.com/coreboot/fsp"
+subhash="68328e297e195a6cfb1949b60d971c032a172ba3"