Fix the get_attr docs in the hot_spec

The current description is "resource ID" and this should read
"resource name".

Change-Id: I0d37f3484e603838c2e11b8984c91c94c793d6c1
Closes-bug: #1381127

doc/source/template_guide/hot_spec.rst

@@ -564,13 +564,13 @@ The syntax of the get_attr function is as follows:
 ::
 
   get_attr:
-    - <resource ID>
+    - <resource name>
     - <attribute name>
     - <key/index 1> (optional)
     - <key/index 2> (optional)
     - ...
 
-resource ID
+resource name
     This parameter specifies the resource for which the attributes shall be
     resolved. This resource must be defined within the *resources* section of
     the template (see also :ref:`hot_spec_resources`).