Small housekeeping: merged two if's with same result into one

Change-Id: I63e038173338055b5b4003e1a6040b8680b8bbd6
Reviewed-on: https://gerrit.libreoffice.org/30901Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>
Tested-by: Mike Kaganski <mike.kaganski@collabora.com>

xmloff/source/text/XMLTextMarkImportContext.cxx

@@ -128,11 +128,10 @@ static SvXMLEnumMapEntry const lcl_aMarkTypeMap[] =
 
 static const char *lcl_getFormFieldmarkName(OUString &name)
 {
-    if (name == "msoffice.field.FORMCHECKBOX" ||
+    if (name == ODF_FORMCHECKBOX ||
+        name == "msoffice.field.FORMCHECKBOX" ||
         name == "ecma.office-open-xml.field.FORMCHECKBOX")
         return ODF_FORMCHECKBOX;
-    else if (name == ODF_FORMCHECKBOX)
-        return ODF_FORMCHECKBOX;
     else if (name == ODF_FORMDROPDOWN ||
              name == "ecma.office-open-xml.field.FORMDROPDOWN")
         return ODF_FORMDROPDOWN;