First do a dump of your config, in case you want to get it back. On the global zone:
# zonecfg -z zzzpit120b export -f zzzpit120b.txt
Now remove it from the config, and umount it, all this in the global zone.
# zonecfg -z zzzpit120b remove fs dir=/oracle/GYT/saptrace
# umount /zones/zzzpit120 b/root/oracle/GYT/saptrace
Thanks to Alejandro Siller