MIPS: lantiq: use export.h in favour of module.h

The code located at arch/mips/lantiq/ included module.h to be able to use
the EXPORT_SYMBOL* macros. These can now be directly included using
export.h.

Signed-off-by: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2937/


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