[lldb] Fix member access in GetExpressionPath

This change fixes two issues in ValueObject::GetExpressionPath method:

 1. Accessing members of struct references used to produce expression
    paths such as "str.&str.member" (instead of the expected
    "str.member"). This is fixed by assigning the flag tha the child
    value is a dereference when calling Dereference() on references
    and adjusting logic in expression path creation.

 2. If the parent of member access is dereference, the produced
    expression path was "*(ptr).member". This is incorrect, since it
    dereferences the member instead of the pointer. This is fixed by
    wrapping dereference expression into parenthesis, resulting with
    "(*ptr).member".

Reviewed By: werat, clayborg

Differential Revision: https://reviews.llvm.org/D132734

lldb/test/API/python_api/expression_path/main.cpp

@@ -0,0 +1,34 @@
+struct StructA {
+  int x;
+  int y;
+};
+
+struct StructB {
+  int x;
+  StructA &a_ref;
+  StructA *&a_ptr_ref;
+};
+
+struct StructC : public StructB {
+  int y;
+
+  StructC(int x, StructA &a_ref, StructA *&a_ref_ptr, int y)
+      : StructB{x, a_ref, a_ref_ptr}, y(y) {}
+};
+
+int main() {
+  StructA a{1, 2};
+  StructA *a_ptr = &a;
+
+  StructB b{3, a, a_ptr};
+  StructB *b_ptr = &b;
+  StructB &b_ref = b;
+  StructB *&b_ptr_ref = b_ptr;
+
+  StructC c(4, a, a_ptr, 5);
+  StructC *c_ptr = &c;
+  StructC &c_ref = c;
+  StructC *&c_ptr_ref = c_ptr;
+
+  return 0; // Set breakpoint here
+}