powerpc/pseries: Fix duplicate firmware feature for DRC_INFO

We had a mid-air collision between two new firmware features, DRMEM_V2
and DRC_INFO, and they ended up with the same value.

No one's actually reported any problems, presumably because the new
firmware that supports both properties is not widely available, and
the two properties tend to be enabled together.

Still if we ever had one enabled but not the other, the bugs that
could result are many and varied. So fix it.

Fixes: 3f38000e

 ("powerpc/firmware: Add definitions for new drc-info firmware feature")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>