Revert "MB-10164: Set numShards based on disk type"

This reverts commit ba2c74f3bfab0fabb951639cf5df8263129db16d.

Change-Id: I2a09bca778d853b74f37f1e488dbf1cc14d68531
Reviewed-on: http://review.couchbase.org/34904
Reviewed-by: Chiyoung Seo <chiyoung@couchbase.com>
Reviewed-by: abhinav dangeti <abhinav@couchbase.com>
Tested-by: abhinav dangeti <abhinav@couchbase.com>