Delete ATTR_DMI_INBAND_BAR_ENABLE when processing MRW attributes

  This attribute is now set in hb_customize_attrs.xml.  Deleting
  from MRW prevents an unintentional override.

Change-Id: Idff06b0a6d8ceba4843030918743d67b7b9d3acd
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/55886
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
CI-Ready: Douglas R. Gilbert <dgilbert@us.ibm.com>
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP HW <op-hw-jenkins+hostboot@us.ibm.com>
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Reviewed-by: Christian R. Geddes <crgeddes@us.ibm.com>
Reviewed-by: Prachi Gupta <pragupta@us.ibm.com>
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>

src/usr/targeting/common/processMrw.pl

@@ -1321,6 +1321,7 @@ sub processDmi
                         $dmiOffset*$dmi)->as_hex(),2));
 
     $targetObj->setAttribute($target,"DMI_INBAND_BAR_BASE_ADDR_OFFSET",$value);
+    $targetObj->deleteAttribute($target,"DMI_INBAND_BAR_ENABLE");
 }