ENH: use dylib output for ossim on MacOS

CMake/External_ossim.cmake

@@ -81,6 +81,7 @@ else()
       -DCMAKE_CXX_FLAGS:STRING=${OSSIM_CXX_FLAGS}
       -DBUILD_OSSIM_MPI_SUPPORT:BOOL=OFF
       -DBUILD_OSSIM_APPS:BOOL=OFF
+      -DBUILD_OSSIM_FRAMEWORKS:BOOL=OFF
       -DCMAKE_PREFIX_PATH:STRING=${CMAKE_INSTALL_PREFIX};${CMAKE_PREFIX_PATH}
     DEPENDS ${${proj}_DEPENDENCIES}
     CMAKE_COMMAND ${SB_CMAKE_COMMAND}