[IMP] crm: No create on crm.activity.report

Purpose:
Goto 'Contacts' menu, select any Partner and click on 'Activities' state
button. The activities are read-only.

'Activities' is not created manually, so why 'Create' and 'Import' button
in Activities tree view?

'Create' and 'Import' buttons are not useful in 'Activities' view.

addons/crm/res_partner_view.xml

@@ -77,7 +77,7 @@
             <field name="name">crm.activity.report.tree</field>
             <field name="model">crm.activity.report</field>
             <field name="arch" type="xml">
-                <tree delete="false">
+                <tree delete="false" create="false">
                     <field name="author_id"/>
                     <field name="subtype_id"/>
                     <field name="subject"/>