Fixup setDiskSize comment
Fixup setDiskSize comment

Followup from http://review.couchbase.org/c/kv_engine/+/128356
correcting a method comment.

Change-Id: I5d5d84c76a6369d40991a16f12e38760cf13c701
Reviewed-on: http://review.couchbase.org/c/kv_engine/+/130430
Tested-by: James Harrison <5c25a7b3db09830813688775bfc8e6de736a230c@couchbase.com>
Reviewed-by: Jim Walker <1cd02e31b43620d7c664e038ca42a060d61727b9@couchbase.com>

daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine