powerpc/64s: Add CPU_FTRS_POWER10 to ALWAYS mask

CPU_FTRS_POWER10 is missing from the CPU_FTRS_ALWAYS mask.

Currently that doesn't cause any bug, because it is a superset of the
POWER9 mask, which the exception of CPU_FTR_TM, but POWER7 doesn't have
CPU_FTR_TM, so CPU_FTR_TM is not in the ALWAYS mask to begin with.

However for consistency, and to be robust against future changes, it
should be included in the ALWAYS mask.

Fixes: a3ea40d5 ("powerpc: Add POWER10 architected mode")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220519122205.746276-2-mpe@ellerman.id.au