sequence_dialog: Reorganize the constructor

The previous code was all "smushed" together wasn't really grouped
together that well.

This spaces things out and separates them by relation to one another,
making it easier to visually parse the individual sections of code that
make up the constructor.

src/yuzu/util/sequence_dialog/sequence_dialog.cpp

@@ -9,15 +9,19 @@
 
 SequenceDialog::SequenceDialog(QWidget* parent) : QDialog(parent) {
     setWindowTitle(tr("Enter a hotkey"));
-    auto* layout = new QVBoxLayout(this);
+    setWindowFlags(windowFlags() & ~Qt::WindowContextHelpButtonHint);
+
     key_sequence = new QKeySequenceEdit;
-    layout->addWidget(key_sequence);
+
-    auto* buttons = new QDialogButtonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel);
+    auto* const buttons = new QDialogButtonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel);
     buttons->setCenterButtons(true);
+
+    auto* const layout = new QVBoxLayout(this);
+    layout->addWidget(key_sequence);
     layout->addWidget(buttons);
+
     connect(buttons, &QDialogButtonBox::accepted, this, &QDialog::accept);
     connect(buttons, &QDialogButtonBox::rejected, this, &QDialog::reject);
-    setWindowFlags(windowFlags() & ~Qt::WindowContextHelpButtonHint);
 }
 
 SequenceDialog::~SequenceDialog() = default;