MIPS: KVM: Use __local_flush_icache_user_range()

Convert KVM dynamic translation of guest instructions to flush icache
for guest mapped addresses using the new
__local_flush_icache_user_range() API to allow the more generic
flush_icache_range() to be changed to work on kernel addresses only.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14155/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>