wallet: Remove unused descriptor checkbox from wallet creation dialog

- Removed the unused descriptor checkbox from the wallet creation dialog.

This change cleans up the UI and resolves compiler errors due to missing the `descriptor_checkbox` member by removing an unused element, improving the user experience.

References:
- DigiByte-Core#213
- DigiByte-Core#227
- DigiByte-Core#239 (comment)

src/qt/createwalletdialog.cpp

@@ -85,18 +85,10 @@ CreateWalletDialog::CreateWalletDialog(QWidget* parent) :
     });
 
 #ifndef USE_SQLITE
-        ui->descriptor_checkbox->setToolTip(tr("Compiled without sqlite support (required for descriptor wallets)"));
-        ui->descriptor_checkbox->setEnabled(false);
-        ui->descriptor_checkbox->setChecked(false);
         ui->external_signer_checkbox->setEnabled(false);
         ui->external_signer_checkbox->setChecked(false);
 #endif
 
-#ifndef USE_BDB
-        ui->descriptor_checkbox->setEnabled(false);
-        ui->descriptor_checkbox->setChecked(true);
-#endif
-
 #ifndef ENABLE_EXTERNAL_SIGNER
         //: "External signing" means using devices such as hardware wallets.
         ui->external_signer_checkbox->setToolTip(tr("Compiled without external signing support (required for external signing)"));

src/qt/forms/createwalletdialog.ui

@@ -142,7 +142,6 @@
   <tabstop>encrypt_wallet_checkbox</tabstop>
   <tabstop>disable_privkeys_checkbox</tabstop>
   <tabstop>blank_wallet_checkbox</tabstop>
-  <tabstop>descriptor_checkbox</tabstop>
   <tabstop>external_signer_checkbox</tabstop>
  </tabstops>
  <resources/>