cmake: don't install headers and import libraries of vendored libs

Users of SDL_mixer should link to SDL_mixer, not the decoder libraries.

Author: madebr

CMakeLists.txt

@@ -1104,10 +1104,8 @@ if(SDL3MIXER_INSTALL)
     if(INSTALL_EXTRA_TARGETS)
         install(TARGETS ${INSTALL_EXTRA_TARGETS}
             EXPORT SDL3MixerTargets
-            ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}" COMPONENT devel
             LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}" COMPONENT library
             RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}" COMPONENT library
-            PUBLIC_HEADER DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}" COMPONENT devel
         )
     endif()