perf scripting python: Don't be strict at handling libtraceevent enumerations

The build was failing on archlinux because it has a newer libtraceevent
that added a new entry to the tep_print_arg_type enum:

    19.72 archlinux:base                : FAIL gcc version 12.2.0 (GCC)
    util/scripting-engines/trace-event-python.c: In function ‘define_event_symbols’:
    util/scripting-engines/trace-event-python.c:281:9: error: enumeration value ‘TEP_PRINT_CPUMASK’ not handled in switch [-Werror=switch-enum]
      281 |         switch (args->type) {
          |         ^~~~~~
    cc1: all warnings being treated as errors

Since we build with distros that have different versions of
libtraceevent and there is no way to easily test if these enum entries
are available, just disable -Werror=switch-enum for that specific
object.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>