Add libuserdefs and use in cmd/{oamuser,passwd}

@@ -317,10 +317,12 @@
 file path=usr/lib/llib-lsip.ln
 file path=usr/lib/llib-lsldap
 file path=usr/lib/llib-lsldap.ln
 file path=usr/lib/llib-lsmbios
 file path=usr/lib/llib-lsmbios.ln
+file path=usr/lib/llib-luserdefs
+file path=usr/lib/llib-luserdefs.ln
 $(sparc_ONLY)file path=usr/lib/llib-lv12n
 $(sparc_ONLY)file path=usr/lib/llib-lv12n.ln
 file path=usr/lib/llib-lvolmgt
 file path=usr/lib/llib-lvolmgt.ln
 file path=usr/lib/llib-lwrap