The firmware API has a feature to enable batching requests for the same fil
e under one worker, so only one lookup is done. This only triggers if we so
happen to schedule two lookups for same file around the same time, or if
release_firmware() has not been called for a successful firmware call. This
can happen for instance if you happen to have multiple devices and one
device driver for certain drivers where the stars line up scheduling
wise.

This adds a new sync and async test trigger. Instead of adding a new
trigger for each new test type we make the tests a bit configurable so that
we could configure the tests in userspace and just kick a test through a
few basic triggers. With this, for instance the two types of sync requests:

  o request_firmware() and
  o request_firmware_direct()

can be modified with a knob. Likewise the two type of async requests:

   o request_firmware_nowait(uevent=true) and
   o request_firmware_nowait(uevent=false)

can be configure...