pnor_partition_table: Move struct vpnor_partition_table to header

Allow use of the definition in other parts of the codebase.

Change-Id: I5f4f23c909a09f12fd16728183aadbf36b565dba
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
diff --git a/pnor_partition_table.hpp b/pnor_partition_table.hpp
index 796a47a..730e75b 100644
--- a/pnor_partition_table.hpp
+++ b/pnor_partition_table.hpp
@@ -306,3 +306,8 @@
 
 } // namespace virtual_pnor
 } // namespace openpower
+
+struct vpnor_partition_table
+{
+    openpower::virtual_pnor::partition::Table* table;
+};