ionic: add dynamic_debug header

Add the appropriate header for using dynamic_hex_dump(), which
seems to be incidentally included in some configurations but
not all.

Fixes: 7e4d4759

 ("ionic: replay filters after fw upgrade")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>