net: update the usage of CHECKSUM_UNNECESSARY
net: update the usage of CHECKSUM_UNNECESSARY

As suggested by Ben, this adds the clarification on the usage of
CHECKSUM_UNNECESSARY on the outgoing patch. Also add the usage
description of NETIF_F_FCOE_CRC and CHECKSUM_UNNECESSARY
for the kernel FCoE protocol driver.

This is a follow-up to the following:
http://patchwork.ozlabs.org/patch/147315/

Signed-off-by: Yi Zou <5b3a821cf7a153d601945bbe257e1150110342e4@intel.com>
Cc: Ben Hutchings <0672176982fbc629cc374f31a7a45ae1671abf90@solarflare.com>
Cc: Jeff Kirsher <87e35f5be20bb3e67f4ba6b86f5f6be3085b1b3a@intel.com>
Cc: www.Open-FCoE.org <21a6cafaf0e9b0080692d699c1538d0dfa42b47a@open-fcoe.org>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs