Avoid veth read/write calls with zero length buffer
Avoid veth read/write calls with zero length buffer

This avoids unnecessary libveth-read/write calls in cimod_check_and_install

Signed-off-by: Avik Sil <17082b09d28e2889ed386af5b5a3b39a391ce64d@linux.vnet.ibm.com>

qemu/SLOF,agraf/SLOF,open-power-host-os/slof,stefanberger/SLOF-tpm,stefanberger/SLOF-tpm,open-power-host-os/slof,aik/SLOF,qemu/SLOF,open-power-host-os/slof,agraf/SLOF,open-power-host-os/slof,aik/SLOF,stefanberger/SLOF-tpm,agraf/SLOF,agraf/SLOF,qemu/SLOF,aik/SLOF