mips: remove ioremap_cachable

mips: remove ioremap_cachable

Just define ioremap_cache directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Guo Ren <guoren@kernel.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: linux-mips@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org