i40e: use the right debug macro

i40e: use the right debug macro

- Don't use DEBUGFUNC macro in pmd.
- Don't use printf for logs.
- We should avoid calling RTE_LOG directly as pmd provides a wrapper for logs.
- Replace some PMD_INIT_LOG(DEBUG, "some_func") with PMD_INIT_FUNC_TRACE().

Signed-off-by: David Marchand <david.marchand@6wind.com>
Reviewed-by: Jay Rolette <rolette@infiniteio.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>