py/objexcept: Rename mp_obj_new_exception_msg_varg2 to ..._vlist.

Follow up to recent commit ad7213d3c3, the
name "varg2" is misleading, vlist describes better that the argument is a
va_list.  This name also matches CircuitPython, which already has such
helper functions.

py/obj.h

@@ -708,7 +708,7 @@ mp_obj_t mp_obj_new_exception_args(const mp_obj_type_t *exc_type, size_t n_args,
 mp_obj_t mp_obj_new_exception_msg(const mp_obj_type_t *exc_type, const char *msg);
 mp_obj_t mp_obj_new_exception_msg_varg(const mp_obj_type_t *exc_type, const char *fmt, ...); // counts args by number of % symbols in fmt, excluding %%; can only handle void* sizes (ie no float/double!)
 #ifdef va_start
-mp_obj_t mp_obj_new_exception_msg_varg2(const mp_obj_type_t *exc_type, const char *fmt, va_list arg); // counts args by number of % symbols in fmt, excluding %%; can only handle void* sizes (ie no float/double!)
+mp_obj_t mp_obj_new_exception_msg_vlist(const mp_obj_type_t *exc_type, const char *fmt, va_list arg); // same fmt restrictions as above
 #endif
 mp_obj_t mp_obj_new_fun_bc(mp_obj_t def_args, mp_obj_t def_kw_args, const byte *code, const mp_uint_t *const_table);
 mp_obj_t mp_obj_new_fun_native(mp_obj_t def_args_in, mp_obj_t def_kw_args, const void *fun_data, const mp_uint_t *const_table);

py/objexcept.c

@@ -387,12 +387,12 @@ STATIC void exc_add_strn(void *data, const char *str, size_t len) {
 mp_obj_t mp_obj_new_exception_msg_varg(const mp_obj_type_t *exc_type, const char *fmt, ...) {
     va_list args;
     va_start(args, fmt);
-    mp_obj_t exc = mp_obj_new_exception_msg_varg2(exc_type, fmt, args);
+    mp_obj_t exc = mp_obj_new_exception_msg_vlist(exc_type, fmt, args);
     va_end(args);
     return exc;
 }
 
-mp_obj_t mp_obj_new_exception_msg_varg2(const mp_obj_type_t *exc_type, const char *fmt, va_list args) {
+mp_obj_t mp_obj_new_exception_msg_vlist(const mp_obj_type_t *exc_type, const char *fmt, va_list args) {
     assert(fmt != NULL);
 
     // Check that the given type is an exception type

py/runtime.c

@@ -1494,7 +1494,7 @@ NORETURN void mp_raise_msg(const mp_obj_type_t *exc_type, const char *msg) {
 NORETURN void mp_raise_msg_varg(const mp_obj_type_t *exc_type, const char *fmt, ...) {
     va_list args;
     va_start(args, fmt);
-    mp_obj_t exc = mp_obj_new_exception_msg_varg2(exc_type, fmt, args);
+    mp_obj_t exc = mp_obj_new_exception_msg_vlist(exc_type, fmt, args);
     va_end(args);
     nlr_raise(exc);
 }