qemuDomainCreateDeviceRecursive: Report error if mkdir() fails
qemuDomainCreateDeviceRecursive: Report error if mkdir() fails

The virFileMakePathWithMode() which is our recursive version of
mkdir() fails, it simply just returns a negative value with errno
set. No error is reported (as compared to virFileTouch() for
instance).

Signed-off-by: Michal Privoznik <83d82aaba2eed257f4814b0c239c260c4caaadf0@redhat.com>
Reviewed-by: Pavel Mores <e8e79a41a9b826cd47122238a26f8527b5f610bc@redhat.com>

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