net: ethernet: ti: am65-cpsw: remove am65_cpsw_nuss_tx_compl_packets_2g()

The only difference between am65_cpsw_nuss_tx_compl_packets_2g() and
am65_cpsw_nuss_tx_compl_packets() is the usage of spin_lock() and
netdev_tx_completed_queue() + am65_cpsw_nuss_tx_wake at every packet
in the latter.

Insted of having 2 separate functions for TX completion, merge them
into one. This will reduce code duplication and make maintenance easier.

Signed-off-by: Roger Quadros <rogerq@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>