There is no point in pushing this burden to the devices, they tend to
forget to call them (like intel-hda, ahci, xhci did). Instead, reset
functions are now called from pci_device_reset. They do nothing if
MSI/MSI-X is not in use.

CC: Alexander Graf <agraf@suse.de>
CC: Gerd Hoffmann <kraxel@redhat.com>
CC: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>