Merge #16969: refactor: Remove Qt function to disable menu icons on macOS

3eea6a8 refactor: Remove Qt function to disable menu icons on macOS (Emil Engler)

Pull request description:

  As menu icons were removed in #16612, this removes an unnecessary function for macOS
  Could this get into v0.19.0?

ACKs for top commit:
  jonasschnelli:
    utACK 3eea6a8
  promag:
    ACK 3eea6a8.
  fanquake:
    ACK 3eea6a8

Tree-SHA512: b3f2f5ed1141f546351433160e27d95dad914739e89dd3438d11756ca5aa41501f0f08345f2b50415717d88517894d73c1065b17f1bda38132374cc58c08df54

Author: fanquake

src/qt/bitcoin.cpp

@@ -436,9 +436,6 @@ int GuiMain(int argc, char* argv[])
 #if QT_VERSION >= 0x050600
     QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
 #endif
-#ifdef Q_OS_MAC
-    QApplication::setAttribute(Qt::AA_DontShowIconsInMenus);
-#endif
 
     BitcoinApplication app(*node);