ixgbe: add check for supported modes
ixgbe: add check for supported modes

When setting advertised speed/duplex with ethtool.

Also cleaned up the comment since we also support 100/F.

Signed-off-by: Emil Tantilov <7bb77ce8696ed668ba78a49cc3445dd5ee9fe4b8@intel.com>
Tested-by: Phil Schmitt <e59a1cb13110d2d5848864a809262db69840c26d@intel.com>
Signed-off-by: Jeff Kirsher <87e35f5be20bb3e67f4ba6b86f5f6be3085b1b3a@intel.com>

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