MIPS: Flush huge TLB

When flushing TLB, if @vma is backed by huge page, we could flush huge
TLB, due to that huge page is defined to be far from normal page.

Signed-off-by: Hillf Danton <dhillf@gmail.com>
Acked-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: "Jayachandran C." <jayachandranc@netlogicmicro.com>
Patchwork: https://patchwork.linux-mips.org/patch/2825/
Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Hillf Danton <dhillf@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/3114/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>