ASoC: SOF: sof-client-probes: Add available points_info(), IPC4 only

ASoC: SOF: sof-client-probes: Add available points_info(), IPC4 only

Add another debugfs file, "probe_points_available", that shows all the
available probe points in the SOF FW at the time of query. The probe
points are there only when an active SOF stream exists in the
system. However, the stream identifiers are persistent in the sense
that the same probe point identifiers always appear with the same
playback or capture command in the same system configuration.

The output, when reading "probe_points_available", may look like this:

0x1000005,0x0,0x100     host-copier.0.playback output buf idx 0 (connected)
0x7,0x0,0x100   gain.1.1 input buf idx 0 (connected)
0x1000007,0x0,0x0       gain.1.1 output buf idx 0
0x3,0x0,0x0     mixin.1.1 input buf idx 0
0x1000003,0x0,0x0       mixin.1.1 output buf idx 0
0x4,0x0,0x0     mixout.2.1 input buf idx 0
0x1000004,0x0,0x0       mixout.2.1 output buf idx 0
0x10007,0x0,0x0 gain.2.1 input buf idx 0
0x1010007,0x0,0x0       gain.2.1 output buf idx 0
0x11,0x0,0x0    smart_amp.2.1 input buf idx 0
0x1000011,0x0,0x0       smart_amp.2.1 output buf idx 0
0x10005,0x0,0x0 dai-copier.SSP.NoCodec-0.playback input buf idx 0

The triplet at the beginning of a line can be copy-pasted as such to
"probe_points" debugfs file for adding a probe point. The rest of the
line tries to give human readable explanation of what this probe point
is.

Signed-off-by: Jyri Sarha <jyri.sarha@linux.intel.com>
Reviewed-by: Liam Girdwood <liam.r.girdwood@intel.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Message-ID: <20250829093022.32094-6-peter.ujfalusi@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>