feat(mge/imperative/opr): modify batch_norm to support frozen BN

fix(mge/imperative): cmake uses MGE_BUILD_IMPERATIVE_RT flag

GitOrigin-RevId: 8ea21af9dab3a7e4fcb13b3849fd094f4e530711

dnn/src/common/batch_normalization.cpp

@@ -58,6 +58,7 @@ void BNBackward::check_exec(const TensorLayout& x, const TensorLayout& dy,
             get_workspace_in_bytes(x, dy, saved_batch_mean, saved_batch_variance,
                                    bn_scale, d_bn_scale, d_bn_bias, dx);
     megdnn_assert(workspace_in_bytes >= required_workspace_in_bytes);
+    megdnn_assert(param().fwd_mode == Param::FwdMode::TRAINING, "BNBackward only support TRAINING mode");
 }
 
 }  // namespace megdnn

src/CMakeLists.txt

@@ -156,7 +156,7 @@ if(ANDROID)
     target_link_libraries(megbrain PUBLIC log)
 endif()
 
-if(NOT MGE_BUILD_XXX)
+if(NOT MGE_BUILD_IMPERATIVE_RT)
     # Build as SHARED or STATIC depending on BUILD_SHARED_LIBS=ON/OFF
     add_library(megengine)
     target_link_libraries(megengine PUBLIC megbrain megdnn)