PCI: replace "secondary" flavors of PCI_{DEVFN,BDF,SBDF}()

PCI: replace "secondary" flavors of PCI_{DEVFN,BDF,SBDF}()

At their use sites the numeric suffixes are at least odd to read, first
and foremost for PCI_DEVFN2() where the suffix doesn't even match the
number of arguments. Make use of count_args() such that a single flavor
each suffices (leaving aside helper macros, which aren't supposed to be
used from the outside).

In parse_ppr_log_entry() take the opportunity and drop two local
variables and convert an assignment to an initializer.

In VT-d code fold a number of bus+devfn comparison pairs into a single
BDF comparison.

No change to generated code for the vast majority of the adjustments.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Paul Durrant <paul@xen.org>