net/i40e: unhelpful warning messages

[Stephen Hemminger]

Got new machine setup with XL710 NIC's and testing out DPDK.

When device is first used by DPDK see these messages.
Which are at warning level which by definition means something is wrong.
And the messages are unhelpful; they mean some to the developer but not to a user.

I40E_DRIVER: i40e_GLQF_reg_init(): i40e device 0000:02:00.0 changed global register [0x002689a0]. original: 0x00000000, new: 0x00000029 
I40E_DRIVER: i40e_GLQF_reg_init(): i40e device 0000:02:00.0 changed global register [0x00268ca4]. original: 0x00001840, new: 0x00009420 
I40E_DRIVER: i40e_aq_debug_write_global_register(): i40e device 0000:02:00.0 changed global register [0x0026c7a0]. original: 0xa8, after: 0x28