hps_accel/conv2c_call.cc: make work with gen2
hps_accel/conv2c_call.cc: make work with gen2

Modify conv2d_call to better simulate a call of CONV2D from TfLM. This
is needed for the gen2 accelerator which

a) requires input data be in the input arena
b) does not have additional memory outside arena for ouput.

Signed-off-by: Alan Green <97e77871b5fcc4941bebceb4338c97c1fd149f8c@google.com>

google/CFU-Playground,google/CFU-Playground,google/CFU-Playground,google/CFU-Playground