fix or improve debug printing

[avg-I]

Log messages produced without the suggested changes:

Apr 15 06:50:14 motil kernel: [drm] SADs count is: -2, don't need to read it
Apr 15 06:50:14 motil kernel: [drm:%s: 0x%05x AUX %s (ret=%3d) %*ph
Apr 15 06:50:14 motil kernel: ] dmdc[drm:dc_conn_log_hex_linux] 00 [drm:dc_conn_log_hex_linux] FF [drm:dc_conn_log_hex_linux] FF [drm:dc_conn_log_hex_linux] FF [drm:dc_conn_log_hex_linux] FF [drm:dc_conn_log_hex_linux] FF [drm:dc_conn_log_hex_linux] FF [drm:dc_conn_log_hex_linux] 00 [drm:dc_conn_log_hex_linux] 0D [drm:dc_conn_log_hex_linux] AE [drm:dc_conn_log_hex_linux] D4 [drm:dc_conn_log_hex_linux] 14 [drm:dc_conn_log_hex_linux] 00 [drm:dc_conn_log_hex_linux] 00 [drm:dc_conn_log_hex_linux] 00 [drm:dc_conn_log_hex_linux] 00 [drm:dc_conn_log_hex_linux] 24 [drm:dc_conn_log_hex_linux] 1A [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 04 [drm:dc_conn_log_hex_linux] A5 [drm:dc_conn_log_hex_linux] 1F [drm:dc_conn_log_hex_linux] 11 [drm:dc_conn_log_hex_linux] 78 [drm:dc_conn_log_hex_linux] 02 [drm:dc_conn_log_hex_linux] 28 [drm:dc_conn_log_hex_linux] 65 [drm:dc_conn_log_hex_linux] 97 [drm:dc_conn_log_hex_linux] 59 [drm:dc_conn_log_hex_linux] 54 [drm:dc_conn_log_hex_linux] 8E [drm:dc_conn_log_hex_linux] 27 [drm:dc_conn_log_hex_linux] 1E [drm:dc_conn_log_hex_linux] 50 [drm:dc_conn_log_hex_linux] 54 [drm:dc_conn_log_hex_linux] 00 [drm:dc_conn_log_hex_linux] 00 [drm:dc_conn_log_hex_linux] 00 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] 01 [drm:dc_conn_log_hex_linux] B4 [drm:dc_conn_log_hex_linux] 3B [drm:dc_conn_log_hex_linux] 80 [drm:dc_conn_log_hex_linux] 4A [drm:dc_conn_log_hex_linux] 71 [drm:dc_conn_log_hex_linux] 38 [drm:dc_conn_log_hex_linux] 34 [drm:dc_conn_log_hex_linux] 40 [drm:dc_conn_log_hex_linux] 50 [drm:dc_conn_log_hex_linux] 3C [drm:dc_conn_log_hex_linux] 68 [drm:dc_conn_log_hex_linux

[avg-I]

With the changes:

Apr 30 14:41:23 motil kernel: [drm] SADs count is: -2, don't need to read it                                                                                                                                                          
Apr 30 14:41:23 motil kernel: [drm:drm_dp_dump_access] dmdc: 0x00218 AUX -> (ret=  1) 00                                                                                                                                              
Apr 30 14:41:23 motil kernel: [drm:dc_conn_log_hex_linux] 00 ff ff ff ff ff ff 00 0d ae d4 14 00 00 00 00 24 1a 01 04 a5 1f 11 78 02 28 65 97 59 54 8e 27 1e 50 54 00 00 00 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 b4 3b 80 4a 71 38 34 40 50 3c 68 00 35 ad 10 00 00 18 00 00 00 fe 00 4e 31 34 30 48 43 41 2d 45 41 43 0a 20 00 00 00 fe 00 43 4d 4e 0a 20 20 20 20 20 20 20 20 20 00 00 00 fe 00 4e 31 34 30 48 43 41 2d 45 41 43 0a 20 00 05

[evadot]

lgtm