add rcore-user submodule

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "riscv-pk"]
 	path = riscv-pk
 	url = https://github.com/riscv-and-rust-and-decaf/riscv-pk.git
+[submodule "user"]
+    path = user
+    url = https://github.com/wangrunji0408/rcore_user.git

kernel/Makefile

@@ -42,12 +42,7 @@ k210_lib := ../tools/k210/libkendryte.a
 export ARCH = $(arch)
 export BOARD = $(board)
 export SMP = $(smp)
-#export SFSIMG = $(user_dir)/build/user-$(arch).img
-ifeq ($(arch), x86_64)
-export SFSIMG = $(user_dir)/img/ucore-i386.img
-else
-export SFSIMG = $(user_dir)/img/ucore-$(arch).img
-endif
+export SFSIMG = $(user_dir)/build/$(arch).img
 ifeq ($(arch), aarch64)
 board := raspi3
 endif

user

@@ -0,0 +1 @@
+Subproject commit 86bb44b00d6af6f8fc63bc6179bc0b6cb5d3373b