Check NIC model in some NIC init functions (Mark McLoughlin)

Check NIC model in some NIC init functions (Mark McLoughlin)

Some NIC init functions are only called when that model is
the only valid model. In that case, it makes sense to use
qemu_check_nic_model() from the NIC init function itself.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6286 c046a42c-6fe2-441c-8c8c-71466251a162