[archiso] Always copytoram for NFS

Avoids problems on shutdown (and during normal usage if networks settings changed)
Signed-off-by: Gerardo Exequiel Pozzi <vmlinuz386@yahoo.com.ar>

archiso/hooks/archiso_pxe_nfs

@@ -22,5 +22,6 @@ archiso_nfs_mount_handler() {
         launch_interactive_shell
     fi
 
+    copytoram="y"
     archiso_mount_handler ${newroot}
 }