powerpc/mm/hash: Always clear UPRT and Host Radix bits when setting up CPU

We will set LPCR with correct value for radix during int. This make sure we
start with a sanitized value of LPCR. In case of kexec, cpus can have LPCR
value based on the previous translation mode we were running.

Fixes: fe036a06 ("powerpc/64/kexec: Fix MMU cleanup on radix")
Cc: stable@vger.kernel.org # v4.9+
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>