MIPS: Octeon: Delete override of cpu_has_mips_r2_exec_hazard.

[ Upstream commit f05ff433 ]

This is no longer needed with the fixed, new and improved definition
of cpu_has_mips_r2_exec_hazard in <asm/cpu-features.h>.

For a discussion, see http://patchwork.linux-mips.org/patch/9539/

.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>