fix cmake in release/1.0.0

test=release/1.0.0

doc/CMakeLists.txt

 add_custom_target(paddle_apis ALL
-                  DEPENDS paddle_v2_apis paddle_fluid_apis)
+                  DEPENDS paddle_v2_apis)
 
 add_custom_target(paddle_docs ALL
                   DEPENDS paddle_v2_docs paddle_v2_docs_cn
-                  paddle_fluid_docs paddle_fluid_docs_cn
                   paddle_mobile_docs paddle_mobile_docs_cn)
 
 add_subdirectory(v2)
-add_subdirectory(fluid)
 add_subdirectory(mobile)