MIPS: pci: Drop owner assignment from platform_drivers

This platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: linux-kernel@vger.kernel.org
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8824/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>