Revert "Reland "adb: daemon: Assign valid fd to usb_handle ep0 file descriptor""

This reverts commit bfe3dac3.

This seems to be correlated with an increase in the rate of devices
going offline. Revert it to see if failure rates improve.

Bug: http://b/150863651
Test: treehugger
Change-Id: Ia6163fd9e31d2bf812628e028249662594ac2024