Fix frame counter and CRC readings

[michaellass]

Only the LSB of the frames_received and frames_with_errors counters provided by the aurora_hls_crc_counter module were wired up. All of our tests probably transferred an even number of frames, hence the counters were always showing up as 0 when read by the host code.

Output for the test case given in scripts/run_N1.sh:

3: Total frames received: 8388608
3: Frames with errors: 0
2: Total frames received: 8388608
2: Frames with errors: 0
1: Total frames received: 8388608
1: Frames with errors: 0
5: Total frames received: 8388608
5: Frames with errors: 0
4: Total frames received: 8388608
4: Frames with errors: 0
0: Total frames received: 8388608
0: Frames with errors: 0

Fixes #1

[papeg]

Ah that exlains a lot.. thanks for finding this!