C++: Move ValueNumberPropertyProvider into its own file to prevent accidental imports

Author: MathiasVP

cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/gvn/PrintValueNumbering.qll

@@ -0,0 +1,17 @@
+private import internal.ValueNumberingImports
+private import ValueNumbering
+
+/**
+ * Provides additional information about value numbering in IR dumps.
+ */
+class ValueNumberPropertyProvider extends IRPropertyProvider {
+  override string getInstructionProperty(Instruction instr, string key) {
+    exists(ValueNumber vn |
+      vn = valueNumber(instr) and
+      key = "valnum" and
+      if strictcount(vn.getAnInstruction()) > 1
+      then result = vn.getDebugString()
+      else result = "unique"
+    )
+  }
+}

cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/gvn/ValueNumbering.qll

@@ -1,21 +1,6 @@
 private import internal.ValueNumberingInternal
 private import internal.ValueNumberingImports
 
-/**
- * Provides additional information about value numbering in IR dumps.
- */
-class ValueNumberPropertyProvider extends IRPropertyProvider {
-  override string getInstructionProperty(Instruction instr, string key) {
-    exists(ValueNumber vn |
-      vn = valueNumber(instr) and
-      key = "valnum" and
-      if strictcount(vn.getAnInstruction()) > 1
-      then result = vn.getDebugString()
-      else result = "unique"
-    )
-  }
-}
-
 /**
  * The value number assigned to a particular set of instructions that produce equivalent results.
  */