virt: vbox: Add error mapping for VERR_INVALID_NAME and VERR_NO_MORE_FILES

Add error mapping for VERR_INVALID_NAME and VERR_NO_MORE_FILES vbox status
codes, these are both used by the vboxsf (shared folder) code.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>