As part of the legacy from the original driver design, we retain home-grown
tracing infrastructure, complete with own ring buffer and timestamps,
which among other things has a performance penalty. This patch removes it.
Signed-off-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Split the driver into the following parts:
  * core  -- resources, register access, capabilities, etc;
  * udc   -- device controller functionality;
  * debug -- logging events.
Signed-off-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>