create_perf_json: Don't drop PCU umasks

The UMask was dropped for consistency with:
https://github.com/intel/event-converter-for-linux-perf/blob/master/uncore_csv_json.py#L67
However, it leads to all events having the same encoding. Don't drop
the umask which makes them consistent with other libraries like
libpfm4:
https://sourceforge.net/p/perfmon2/libpfm4/ci/master/tree/lib/events/intel_skx_unc_pcu_events.h#l30

A long standing todo () convert to right filter for occupancy

scripts/create_perf_json.py

@@ -335,9 +335,6 @@ def get(key: str) -> str:
                 self.unit = unit_fixups[self.unit]
             elif self.unit == "NCU" and self.event_name == "UNC_CLOCK.SOCKET":
                 self.unit = "CLOCK"
-            elif self.unit == "PCU" and self.umask:
-                # TODO: convert to right filter for occupancy
-                self.umask = None
         if jd.get('CounterType') == "FREERUN":
             self.unit = f"{self.unit.lower()}_free_running"
             m = re.search(r'_MC(\d+)_', self.event_name)