MIPS: Clean up whitespace warning in hazards.h

Use a tab on second and subsequent lines of multiline #if's, for
consistency with the next commit.
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2954/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>