Ensure MSVC startup project is LMMS

src/CMakeLists.txt

@@ -107,6 +107,12 @@ ADD_EXECUTABLE(lmms
 	"${WINRC}"
 )
 
+# Set Visual Studio startup project to lmms
+# https://stackoverflow.com/a/37994396/8166701
+IF(NOT CMAKE_VERSION VERSION_LESS 3.6)
+	SET_PROPERTY(DIRECTORY ${CMAKE_SOURCE_DIR} PROPERTY VS_STARTUP_PROJECT lmms)
+ENDIF()
+
 SET_DIRECTORY_PROPERTIES(PROPERTIES ADDITIONAL_MAKE_CLEAN_FILES "${LMMS_RCC_OUT} ${LMMS_UI_OUT} lmmsconfig.h lmms.1.gz")
 
 IF(LMMS_BUILD_WIN32)