added bitcode ios

CMakeLists.txt

@@ -119,6 +119,7 @@ IF (IOS)
   IF (NOT CMAKE_BUILD_TYPE)
     SET(CMAKE_BUILD_TYPE "Release")
   ENDIF (NOT CMAKE_BUILD_TYPE)
+  ADD_DEFINITIONS(-DENABLE_BITCODE)
 ENDIF (IOS)
 
 # Use subset of Windows.h
@@ -126,6 +127,7 @@ if (WIN32)
   ADD_DEFINITIONS( -DWIN32_LEAN_AND_MEAN )
 endif()
 
+
 IF(MSVC)
   OPTION( ASSIMP_INSTALL_PDB
     "Install MSVC debug files."