compile: Add a missing function 'pciDeviceListFind' to libvirt_private.syms

compile: Add a missing function 'pciDeviceListFind' to libvirt_private.syms

compile error:
./src/.libs/libvirt_driver_qemu.a(libvirt_driver_qemu_la-qemu_hostdev.o): In function `qemuPrepareHostdevPCIDevices':
/home/soulxu/data/work-code/libvirt/src/qemu/qemu_hostdev.c:183: undefined reference to `pciDeviceListFind'
/home/soulxu/data/work-code/libvirt/src/qemu/qemu_hostdev.c:230: undefined reference to `pciDeviceListFind'
./src/.libs/libvirt_driver_qemu.a(libvirt_driver_qemu_la-qemu_hostdev.o): In function `qemuGetActivePciHostDeviceList':
/home/soulxu/data/work-code/libvirt/src/qemu/qemu_hostdev.c:102: undefined reference to `pciDeviceListFind'
./src/.libs/libvirt_driver_qemu.a(libvirt_driver_qemu_la-qemu_hostdev.o): In function `qemuDomainReAttachHostdevDevices':
/home/soulxu/data/work-code/libvirt/src/qemu/qemu_hostdev.c:370: undefined reference to `pciDeviceListFind'

Signed-off-by: Xu He Jie <xuhj@linux.vnet.ibm.com>