At the 'Start' screen go to 'Options' and then to 'Cheat Codes' or during gameplay
Press'Start' and go to 'Settings' and then to 'Cheat Codes' to enter the following codes to unlock the corresponding.

Get ALL Ammo:
Down, Up, Down, Y

Toggle God Mode:
Up, Left Trigger, X, Left Trigger

Toggle Location Stat:
X, Right, Left Trigger, Left

Win Current Match:
L-Trigger, Left Trigger, Left Trigger, Y

Lose Current Match:
Left Trigger, Left Trigger, Left Trigger, A

Unlock Single Player:
Y, Down, Right Trigger, Down