PCI: pci-bridge-emul: Add definitions for missing capabilities registers

PCI: pci-bridge-emul: Add definitions for missing capabilities registers

BugLink: https://bugs.launchpad.net/bugs/1978240
commit 8ea673a8b30b4a32516b8adabb15e2a68ff02ec8 upstream.

pci-bridge-emul driver already allocates buffer for capabilities up to the
PCI_EXP_SLTSTA2 register, but does not define bit access behavior for these
registers. Add these missing definitions.

Link: https://lore.kernel.org/r/20211130172913.9727-3-kabel@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>