py/asmrv32: Add RISC-V RV32IMC native code emitter.

This adds a native code generation backend for RISC-V RV32I CPUs, currently
limited to the I, M, and C instruction sets.

Signed-off-by: Alessandro Gatti <[email protected]>

Author: agatti

py/asmbase.h

@@ -27,6 +27,7 @@
 #define MICROPY_INCLUDED_PY_ASMBASE_H
 
 #include <stdint.h>
+#include <stddef.h>
 #include <stdbool.h>
 
 #define MP_ASM_PASS_COMPUTE (1)