[OSX] revert renaming of Bitcoin-Qt.app

Makefile.am

@@ -14,7 +14,7 @@ BITCOIN_QT_BIN=$(top_builddir)/src/qt/bitcoin-qt$(EXEEXT)
 BITCOIN_CLI_BIN=$(top_builddir)/src/bitcoin-cli$(EXEEXT)
 BITCOIN_WIN_INSTALLER=$(PACKAGE)-$(PACKAGE_VERSION)-win$(WINDOWS_BITS)-setup$(EXEEXT)
 
-OSX_APP=Bitcoin-Core.app
+OSX_APP=Bitcoin-Qt.app
 OSX_DMG=Bitcoin-Core.dmg
 OSX_BACKGROUND_IMAGE=background.tiff
 OSX_DEPLOY_SCRIPT=$(top_srcdir)/contrib/macdeploy/macdeployqtplus