ASoC: tracing: Export SND_SOC_DAPM_DIR_OUT to its value

The string SND_SOC_DAPM_DIR_OUT is printed in the snd_soc_dapm_path trace
event instead of its value:

   (((REC->path_dir) == SND_SOC_DAPM_DIR_OUT) ? "->" : "<-")

User space cannot parse this, as it has no idea what SND_SOC_DAPM_DIR_OUT
is. Use TRACE_DEFINE_ENUM() to convert it to its value:

   (((REC->path_dir) == 1) ? "->" : "<-")

So that user space tools, such as perf and trace-cmd, can parse it
correctly.
Reported-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Fixes: 6e588a0d ("ASoC: dapm: Consolidate path trace events")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20240416000303.04670cdf@rorschach.local.homeSigned-off-by: Mark Brown <broonie@kernel.org>

include/trace/events/asoc.h

@@ -12,6 +12,8 @@
 #define DAPM_DIRECT "(direct)"
 #define DAPM_ARROW(dir) (((dir) == SND_SOC_DAPM_DIR_OUT) ? "->" : "<-")
 
+TRACE_DEFINE_ENUM(SND_SOC_DAPM_DIR_OUT);
+
 struct snd_soc_jack;
 struct snd_soc_card;
 struct snd_soc_dapm_widget;