The IDE=y part seems to be incorrect - quirk_intel_ide_combined() is
needed even with modular IDE. Without this quirk you will get one of
these configurations depending on the module load order:
1) ata_piix loads first - it grabs the whole controller, including the
PATA port; the IDE module loaded later finds nothing.
2) IDE modules are loaded first - without the quirk IDE drivers will
grab the whole controller, including the SATA part.
The binding you get with builtin IDE (ata_piix/ahci for SATA, generic
IDE driver for PATA) would be impossible to get with modular IDE without
the quirk, which does not seem to be good...