powerpc: Update TM user feature bits in scan_features()

We need to update the user TM feature bits (PPC_FEATURE2_HTM and
PPC_FEATURE2_HTM) to mirror what we do with the kernel TM feature
bit.

At the moment, if firmware reports TM is not available we turn off
the kernel TM feature bit but leave the userspace ones on. Userspace
thinks it can execute TM instructions and it dies trying.

This (together with a QEMU patch) fixes PR KVM, which doesn't currently
support TM.

Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>