fm10k: add support for extra debug statistics

fm10k: add support for extra debug statistics

Add a private ethtool flag to enable display of these statistics, which
are generally less useful. However, sometimes it can be useful for
debugging purposes. The most useful portion is the ability to see what
the PF thinks the VF mailboxes look like.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Orabug: 25394529

(cherry picked from commit 80043f3bf5bdb187566620a8f183c15b94e961cb)
Signed-off-by: Jack Vogel <jack.vogel@oracle.com>