ice: Use a different ICE_DBG bit for firmware log messages

Replace the use of the ICE_DBG_AQ_MSG bit when dumping firmware logging
messages with a separate distinct type ICE_DBG_FW_LOG. This is useful
so that developers may enable ICE_DBG_FW_LOG and get firmware logging
messages, without also dumping AdminQ messages at the same time.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>