dogo: support mass storage USB modes

Change-Id: I709c48481fe01e80246a06d9a21a15e375cd2e97
Signed-off-by: Arnav Gupta <championswimmer@aokp.co>
dogo: allow external SD to be mounted as Mass Storage volume

Change-Id: I677fcee94fea211073bafa8f3eb9fd0e4989aa5d
Signed-off-by: Arnav Gupta <championswimmer@aokp.co>