C#: Adjust to use the qlpack data-flow api.

Author: aschackmull

csharp/ql/lib/qlpack.yml

@@ -6,6 +6,7 @@ extractor: csharp
 library: true
 upgrades: upgrades
 dependencies:
+  codeql/dataflow: ${workspace}
   codeql/mad: ${workspace}
   codeql/ssa: ${workspace}
   codeql/tutorial: ${workspace}

csharp/ql/lib/semmle/code/csharp/dataflow/DataFlow.qll

@@ -6,6 +6,8 @@
 import csharp
 
 module DataFlow {
-  import semmle.code.csharp.dataflow.internal.DataFlow
+  private import semmle.code.csharp.dataflow.internal.DataFlowImplSpecific
+  private import codeql.dataflow.DataFlow
+  import DataFlowMake<CsharpDataFlow>
   import semmle.code.csharp.dataflow.internal.DataFlowImpl1
 }