USB: android: Enable streaming only during composition enable

ADB may reset the connection by writing into EP0 file
on every disconnect. unbind config disables the streaming
enabled flag. On next USB connect streaming mode is not
enabled because the flag was disabled already.

Enable streaming mode during composition enable and mark
the streaming enabled flag just before that. If the interface
needs to enable streaming mode then it is enabled at that
time.

Change-Id: I22eb5e6c7de50e7a81ab29296ca96b97229cc9cf
Signed-off-by: Sujeet Kumar <ksujeet@codeaurora.org>