py: Integrate Xtensa assembler into native emitter.
The config option MICROPY_EMIT_XTENSA can now be enabled to target the
Xtensa architecture with @micropython.native and @micropython.viper
decorators.
diff --git a/py/compile.c b/py/compile.c
index 418c110..7c2c89f 100644
--- a/py/compile.c
+++ b/py/compile.c
@@ -79,6 +79,8 @@
#define NATIVE_EMITTER(f) emit_native_thumb_##f
#elif MICROPY_EMIT_ARM
#define NATIVE_EMITTER(f) emit_native_arm_##f
+#elif MICROPY_EMIT_XTENSA
+#define NATIVE_EMITTER(f) emit_native_xtensa_##f
#else
#error "unknown native emitter"
#endif