Drop "APLIC configured for ACLIC operation" section #619
Description
This seems to imply that it is possible for the system to contain an APLIC as well as one or more ACLICs.
However the mechanism for wired-interrupt delivery from APLIC to ACLIC is not specified anywhere.
Proposal:
add MSI-receiving capability as an ACLIC extension (see issue #616 )
then unmodified APLIC can use MSI delivery to ACLIC in systems that require both types of interrupt controller to be present.