Valgrind: Remove some unused QObject parent

Change-Id: Ieef2c25d64b4a82743ce25da54c9d364548eb8d6
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/valgrind/callgrind/callgrindparser.cpp

@@ -644,9 +644,8 @@ void Parser::parse(QIODevice *device)
     d->parse(device);
 }
 
-Parser::Parser(QObject *parent)
-    : QObject(parent),
-      d(new Private(this))
+Parser::Parser()
+    : d(new Private(this))
 {
 }
 

src/plugins/valgrind/callgrind/callgrindparser.h

@@ -50,7 +50,7 @@ class Parser : public QObject
     Q_OBJECT
 
 public:
-    explicit Parser(QObject *parent = nullptr);
+    Parser();
     ~Parser() override;
 
     // get and take ownership of the parsing results. If this function is not called the repository