MIPS: Fix r4k clockevents registration

CPUFreq need min_delta_ticks/max_delta_ticks to be initialized, and
this can be done by clockevents_config_and_register().

Cc: stable@vger.kernel.org
Signed-off-by: Heiher <r@hev.cc>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J . Hill <Steven.Hill@imgtec.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: stable@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13817/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>