[update] support command: scons --target=xmake

tools/xmake.lua

@@ -0,0 +1,46 @@
+add_rules("mode.debug", "mode.release")
+
+toolchain("${toolchain}")
+    set_kind("standalone")
+    set_sdkdir("${sdkdir}")
+toolchain_end()
+
+target("${target}")
+    set_kind("binary")
+    set_toolchains("${toolchain}")
+
+    add_files(
+        ${src_path}
+    )
+
+    add_includedirs(
+        ${inc_path}
+    )
+
+    add_defines(
+        ${define}
+    )
+
+    add_cflags(
+        "${cflags}" ,{force = true}
+    )
+    add_cxxflags(
+        "${cxxflags}" ,{force = true}
+    )
+
+    add_asflags(
+        "${asflags}" ,{force = true}
+    )
+
+    add_ldflags(
+        "${ldflags}" ,{force = true}
+    )
+
+    set_targetdir("./")
+    set_filename("rtthread.elf")
+
+    after_build(function(target)
+        os.exec("${toolchain}-objcopy -O ihex rtthread.elf rtthread.hex")
+        os.exec("${toolchain}-objcopy -O binary rtthread.elf rtthread.bin")
+        os.exec("${toolchain}-size rtthread.elf")
+    end)