Support all backend serial devices for pSeries guest
Support all backend serial devices for pSeries guest

Currently, it only considers PTY backend serial devices for pseries.
It need to support all kinds of serial devices.

This patch is to fix the problem which is that it doesn't work
when specifying source type as file.

Signed-off-by: Li Zhang <63d1e54bd8032f9fe1aee582998ae5c623006e3c@linux.vnet.ibm.com>

shugaoye/libvirt,libvirt/libvirt,cbosdo/libvirt,crobinso/libvirt,iam-TJ/libvirt,siboulet/libvirt-openvz,trainstack/libvirt,bjzhang/libvirt,libvirt/libvirt,zhlcindy/libvirt-1.1.4-maintain,VenkatDatta/libvirt,nertpinx/libvirt,bjzhang/libvirt,crobinso/libvirt,trainstack/libvirt,siboulet/libvirt-openvz,andreabolognani/libvirt,jfehlig/libvirt,elmarco/libvirt,nertpinx/libvirt,andreabolognani/libvirt,VenkatDatta/libvirt,jardasgit/libvirt,zhlcindy/libvirt-1.1.4-maintain,cbosdo/libvirt,VenkatDatta/libvirt,taget/libvirt,trainstack/libvirt,andreabolognani/libvirt,eskultety/libvirt,olafhering/libvirt,siboulet/libvirt-openvz,datto/libvirt,iam-TJ/libvirt,rlaager/libvirt,nertpinx/libvirt,olafhering/libvirt,cbosdo/libvirt,datto/libvirt,iam-TJ/libvirt,VenkatDatta/libvirt,agx/libvirt,jfehlig/libvirt,nertpinx/libvirt,fabianfreyer/libvirt,shugaoye/libvirt,jardasgit/libvirt,datto/libvirt,jardasgit/libvirt,iam-TJ/libvirt,iam-TJ/libvirt,taget/libvirt,agx/libvirt,trainstack/libvirt,trainstack/libvirt,elmarco/libvirt,taget/libvirt,datto/libvirt,crobinso/libvirt,eskultety/libvirt,trainstack/libvirt,shugaoye/libvirt,zippy2/libvirt,olafhering/libvirt,zippy2/libvirt,olafhering/libvirt,eskultety/libvirt,jardasgit/libvirt,iam-TJ/libvirt,eskultety/libvirt,bjzhang/libvirt,fabianfreyer/libvirt,bjzhang/libvirt,zhlcindy/libvirt-1.1.4-maintain,cbosdo/libvirt,fabianfreyer/libvirt,nertpinx/libvirt,rlaager/libvirt,andreabolognani/libvirt,elmarco/libvirt,andreabolognani/libvirt,eskultety/libvirt,taget/libvirt,libvirt/libvirt,fabianfreyer/libvirt,taget/libvirt,zippy2/libvirt,agx/libvirt,trainstack/libvirt,siboulet/libvirt-openvz,libvirt/libvirt,zhlcindy/libvirt-1.1.4-maintain,bjzhang/libvirt,rlaager/libvirt,elmarco/libvirt,agx/libvirt,zippy2/libvirt,elmarco/libvirt,jfehlig/libvirt,crobinso/libvirt,agx/libvirt,VenkatDatta/libvirt,cbosdo/libvirt,fabianfreyer/libvirt,iam-TJ/libvirt,jfehlig/libvirt,jardasgit/libvirt,zhlcindy/libvirt-1.1.4-maintain,datto/libvirt,rlaager/libvirt,rlaager/libvirt,siboulet/libvirt-openvz,shugaoye/libvirt,shugaoye/libvirt