MIPS: malta: Remove software reset defines from generic header.

Remove the software reset register and reset value definitions
from the 'include/asm/mips-boards/generic.h' header file. Also
clean up header and whitespace in platform file.

Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5456/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>