net: tftp: fix '#' line length when receiving large files

When receiving more than TftpBlkSize * 0x10000 bytes,
lines of '####" would not wrap properly. Fix this by deleting
TftpBlockWrapOffset and making TftpBlock always a 32 bit value.

Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>
ksz9031: change rx_ctl/tx_ctl pad skew delay to min
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ksz9031: fix disable_giga