qmake: vcproj: Fix windeployqt config for dll targets

Instead of hardcoding the target's extension to ".exe" we should rely on
target information available in Visual Studio. $(TargetFileName) is
documented as "The file name of the primary output file for the build
(defined as base name + file extension)." so it can be used instead of
$(TargetName) together with ".exe".

Change-Id: I103d8d13456910617b2d53c9c8f4e2935eb93015
Reviewed-by: Kai Koehne <kai.koehne@qt.io>

qmake/generators/win32/msvc_vcproj.cpp

@@ -1350,7 +1350,7 @@ void VcprojGenerator::initWinDeployQtTool()
         //  structure manually by invoking windeployqt a second time, so that
         //  the MDILXapCompile call succeeds and deployment continues.
         conf.windeployqt.CommandLine += commandLine
-                + QStringLiteral(" -list relative -dir \"$(MSBuildProjectDirectory)\" \"$(OutDir)\\$(TargetName).exe\" > ")
+                + QStringLiteral(" -list relative -dir \"$(MSBuildProjectDirectory)\" \"$(OutDir)\\$(TargetFileName)\" > ")
                 + MakefileGenerator::shellQuote(conf.windeployqt.Record);
         conf.windeployqt.config = &vcProject.Configuration;
         conf.windeployqt.ExcludedFromBuild = false;