stm: Add specific UINT_FMT and INT_FMT.

For some reason, STM port, while it's 32 bit, needs %lu and %ld for
printing machine_uint_t and machine_int_t.

stm/mpconfigport.h

@@ -13,6 +13,9 @@
 
 #define BYTES_PER_WORD (4)
 
+#define UINT_FMT "%lu"
+#define INT_FMT "%ld"
+
 typedef int32_t machine_int_t; // must be pointer size
 typedef uint32_t machine_uint_t; // must be pointer size
 typedef void *machine_ptr_t; // must be of pointer size