coresight: trbe: Fix incorrect access of the sink specific data

The TRBE driver wrongly treats the aux private data as the TRBE driver
specific buffer for a given perf handle, while it is the ETM PMU's
event specific data. Fix this by correcting the instance to use
appropriate helper.

Cc: stable <stable@vger.kernel.org>
Fixes: 3fbf7f01 ("coresight: sink: Add TRBE driver")
Signed-off-by: NSuzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: NAnshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20210921134121.2423546-2-suzuki.poulose@arm.com
[Fixed 13 character SHA down to 12]
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>

drivers/hwtracing/coresight/coresight-trbe.c

@@ -382,7 +382,7 @@ static unsigned long __trbe_normal_offset(struct perf_output_handle *handle)
 
 static unsigned long trbe_normal_offset(struct perf_output_handle *handle)
 {
-	struct trbe_buf *buf = perf_get_aux(handle);
+	struct trbe_buf *buf = etm_perf_sink_config(handle);
 	u64 limit = __trbe_normal_offset(handle);
 	u64 head = PERF_IDX2OFF(handle->head, buf);