adbd: don't abort on EOF on functionfs control fd.

Also, improve the logging in the cases where we do abort.

Bug: http://b/131867920
Test: treehugger
Change-Id: If8ec9f4614ce146e6dbd21cc77587ea81658199b
(cherry picked from commit 6d5600056a6d6be390758262686d1893418ba6ea)
1 file changed