eng: Remove the duplicate definition

The RE for data type "name" storagepool.rng uses is same with
"genericName" in basictypes.rng.

docs/schemas/storagepool.rng

@@ -144,7 +144,7 @@
 
   <define name='commonmetadata'>
     <element name='name'>
-      <ref name='name'/>
+      <ref name='genericName'/>
     </element>
     <optional>
       <element name='uuid'>
@@ -230,7 +230,7 @@
       <attribute name='path'>
         <choice>
           <ref name='absFilePath'/>
-          <ref name='name'/>
+          <ref name='genericName'/>
         </choice>
       </attribute>
       <choice>
@@ -519,12 +519,6 @@
     </element>
   </define>
 
-  <define name='name'>
-    <data type='string'>
-      <param name="pattern">[a-zA-Z0-9_\+\-]+</param>
-    </data>
-  </define>
-
   <define name="PortNumber">
     <data type="short">
       <param name="minInclusive">-1</param>