perf intel-pt: decoder: Factor out clearing of FUP (Flow Update) event variables

perf intel-pt: decoder: Factor out clearing of FUP (Flow Update) event variables

Factor out clearing of FUP (Flow Update) event variables, to avoid code duplication.

Committer Notes:

From the Intel documentation:

<quote>
Flow Update Packets (FUP): FUPs provide the source IP addresses for
asynchronous events (interrupt and exceptions), as well as other cases
where the source address cannot be determined from the binary.
</quote>

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/r/20220124084201.2699795-7-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>