If any one needs it, here is the full working config for PS3 which you can copy paste into the snes9x.cfg file.
/opt/retropie/configs/snes/snes9x.cfg
It will replace the 360 pad layout and there is no player 2 but you can edit the file as you wish.
[Keyboard]
# Get codes from /usr/include/SDL/SDL_keysym.h
A_1=100
B_1=99
X_1=115
Y_1=120
L_1=97
R_1=102
START_1=13
SELECT_1=9
LEFT_1=276
RIGHT_1=275
UP_1=273
DOWN_1=274
QUIT=27
ACCEL=8
[Joystick]
# Get codes from "jstest /dev/input/js0"
# from package "joystick"
# Quick save is on right analogue click
# Save is on R2
# Mapped to SNES layout for PS3 controller
# Quit is the PS button
# PS3
A_1=13
B_1=14
X_1=12
Y_1=15
L_1=10
R_1=11
START_1=3
SELECT_1=0
QUIT=16
ACCEL=98
QLOAD=2
QSAVE=9
#Joystick axis
JA_LR=0
JA_UD=1
#Joystick DPAD buttons
LEFT_1=7
RIGHT_1=5
UP_1=4
DOWN_1=6
[Graphics]
DisplaySmoothStretch=1
# Display Effect: 0 none, 1 scanlines, 2 phospher
# NOTE Phospher does not run at full speed
DisplayEffect=0
MaintainAspectRatio=1
DisplayBorder=0
AutoFrameskip=1
Frameskip=200
Transparency=1
CPUCycles=100
[Sound]
APUEnabled=1
# Sound rates below as index, i.e. 7=44100 (some of these produce static)
# 0, 8192, 11025, 16000, 22050, 29300, 32000, 44100
SoundPlaybackRate=7
# Enable on RPI2 for clearer sound, disable on RPI1 due to performance impact
InterpolatedSound=0
Thanks to BuZz getting this all working.