innodb_buffer_pool_populate has not had an effect since 10.0.23
in commit 1e270d50 when its
functionality was removed.

As we've only just enabled LIBNUMA in MDEV-10829 it isn't logical
to have innodb_buffer_pool_populate aliasing for innodb_numa_interleave
this late in the game.

So the simpliest way is just to remove innodb_buffer_pool_populate.
Signed-off-by: Daniel Black <daniel.black@au.ibm.com>