Revert "Remove hotplug from simpleramfs"

This reverts commit f3b254f2cb045a8ebe3dc01e8ead51ee26c88bd3.

Causes problems for spacecast. See discussion in b/34131115.

Change-Id: Ib760b8c7b2ba6294d918c7cb830004c27e7a5ad0
1 file changed