qemu: gpu: Sanitize error values in qemuVhostUserGPUGetPid
qemu: gpu: Sanitize error values in qemuVhostUserGPUGetPid

The caller doesn't care about the actual return value, so return -1
rather than errno.

Signed-off-by: Peter Krempa <2cf5c04c61aa466e4a47bfedc747d17279c72ffc@redhat.com>
Reviewed-by: Ján Tomko <4cab11cfb98d3c937327354a78eb07dbb6ee2bc6@redhat.com>

libvirt/libvirt,nertpinx/libvirt,crobinso/libvirt,nertpinx/libvirt,jardasgit/libvirt,jardasgit/libvirt,crobinso/libvirt,zippy2/libvirt,olafhering/libvirt,crobinso/libvirt,olafhering/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,zippy2/libvirt,libvirt/libvirt,libvirt/libvirt,olafhering/libvirt,fabianfreyer/libvirt,nertpinx/libvirt,jfehlig/libvirt,nertpinx/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,libvirt/libvirt,nertpinx/libvirt,fabianfreyer/libvirt,olafhering/libvirt,jfehlig/libvirt,jardasgit/libvirt,jfehlig/libvirt,jfehlig/libvirt,crobinso/libvirt,zippy2/libvirt,fabianfreyer/libvirt,zippy2/libvirt