Revert "usb: dwc3: debugfs: Add and remove endpoint dirs dynamically"

This reverts commit 3bef2103.

Reason for revert: Boot fail with this patch.
Bug: 194984062
Signed-off-by: Lucas Wei <lucaswei@google.com>
Change-Id: Ice1c308f6ff0255a5f541a6351ceebcda6b3ddca