lwip: tcp_rexmit_rto: Remove superfluous #if TCP_OVERSIZE guard
lwip: tcp_rexmit_rto: Remove superfluous #if TCP_OVERSIZE guard

Upstream commit: a93ae2558f97b32917599591ecfec949e58372a9

ambrop72/aprinter,ambrop72/aprinter,ambrop72/aprinter,johnkingsley/aprinter,johnkingsley/aprinter,ambrop72/aprinter,johnkingsley/aprinter,johnkingsley/aprinter,ambrop72/aprinter,ambrop72/aprinter,johnkingsley/aprinter,johnkingsley/aprinter,ambrop72/aprinter,johnkingsley/aprinter