[C] Snow made by snow golems not dropping snowballs. Fixes BUKKIT-5004

##### The Issue:
Snow created by a snow golem does not drop snowball items.

##### PR Breakdown:
Fixing location of snow block, that was set wrong because of changes in NMS code.

##### JIRA Ticket: 
[JIRA Ticket #5004](https://bukkit.atlassian.net/browse/BUKKIT-5004)