stmhal: pyb: Use gc() function as defined by standard module "gc".

TODO: Get rid of this compatibility define and rely on standard module.

stmhal/gccollect.c

@@ -72,10 +72,3 @@ void gc_collect(void) {
         printf(" 1=" UINT_FMT " 2=" UINT_FMT " m=" UINT_FMT "\n", info.num_1block, info.num_2block, info.max_block);
     }
 }
-
-static mp_obj_t pyb_gc(void) {
-    gc_collect();
-    return mp_const_none;
-}
-
-MP_DEFINE_CONST_FUN_OBJ_0(pyb_gc_obj, pyb_gc);

stmhal/gccollect.h

@@ -40,4 +40,4 @@ extern uint32_t _ram_end;
 
 void gc_collect(void);
 
-MP_DECLARE_CONST_FUN_OBJ(pyb_gc_obj);
+MP_DECLARE_CONST_FUN_OBJ(gc_collect_obj);

stmhal/modpyb.c

@@ -305,7 +305,7 @@ STATIC const mp_map_elem_t pyb_module_globals_table[] = {
     { MP_OBJ_NEW_QSTR(MP_QSTR_info), (mp_obj_t)&pyb_info_obj },
     { MP_OBJ_NEW_QSTR(MP_QSTR_unique_id), (mp_obj_t)&pyb_unique_id_obj },
     { MP_OBJ_NEW_QSTR(MP_QSTR_freq), (mp_obj_t)&pyb_freq_obj },
-    { MP_OBJ_NEW_QSTR(MP_QSTR_gc), (mp_obj_t)&pyb_gc_obj },
+    { MP_OBJ_NEW_QSTR(MP_QSTR_gc), (mp_obj_t)&gc_collect_obj },
     { MP_OBJ_NEW_QSTR(MP_QSTR_repl_info), (mp_obj_t)&pyb_set_repl_info_obj },
 
     { MP_OBJ_NEW_QSTR(MP_QSTR_wfi), (mp_obj_t)&pyb_wfi_obj },