py/objstr: Consolidate methods for str/bytes/bytearray/array.

This commit adds the bytes methods to bytearray, matching CPython.  The
existing implementations of these methods for str/bytes are reused for
bytearray with minor updates to match CPython return types.

For details on the CPython behaviour see
https://docs.python.org/3/library/stdtypes.html#bytes-and-bytearray-operations

The work to merge locals tables for str/bytes/bytearray/array was done by
@jimmo.  Because of this merging of locals the change in code size for this
commit is mostly negative:

       bare-arm:    +0 +0.000%
    minimal x86:   +29 +0.018%
       unix x64:  -792 -0.128% standard[incl -448(data)]
    unix nanbox:  -436 -0.078% nanbox[incl -448(data)]
          stm32:   -40 -0.010% PYBV10
         cc3200:   -32 -0.017%
        esp8266:   -28 -0.004% GENERIC
          esp32:   -72 -0.005% GENERIC[incl -200(data)]
         mimxrt:   -40 -0.011% TEENSY40
     renesas-ra:   -40 -0.006% RA6M2_EK
            nrf:   -16 -0.009% pca10040
            rp2:   -64 -0.013% PICO
           samd:  +148 +0.105% ADAFRUIT_ITSYBITSY_M4_EXPRESS

py/obj.h

@@ -394,19 +394,21 @@ typedef struct _mp_rom_obj_t { mp_const_obj_t o; } mp_rom_obj_t;
         .table = (mp_map_elem_t *)(mp_rom_map_elem_t *)table_name, \
     }
 
-#define MP_DEFINE_CONST_DICT(dict_name, table_name) \
+#define MP_DEFINE_CONST_DICT_WITH_SIZE(dict_name, table_name, n) \
     const mp_obj_dict_t dict_name = { \
         .base = {&mp_type_dict}, \
         .map = { \
             .all_keys_are_qstrs = 1, \
             .is_fixed = 1, \
             .is_ordered = 1, \
-            .used = MP_ARRAY_SIZE(table_name), \
-            .alloc = MP_ARRAY_SIZE(table_name), \
+            .used = n, \
+            .alloc = n, \
             .table = (mp_map_elem_t *)(mp_rom_map_elem_t *)table_name, \
         }, \
     }
 
+#define MP_DEFINE_CONST_DICT(dict_name, table_name) MP_DEFINE_CONST_DICT_WITH_SIZE(dict_name, table_name, MP_ARRAY_SIZE(table_name))
+
 // These macros are used to declare and define constant staticmethond and classmethod objects
 // You can put "static" in front of the definitions to make them local
 
@@ -789,7 +791,7 @@ mp_obj_t mp_obj_new_str(const char *data, size_t len);
 mp_obj_t mp_obj_new_str_via_qstr(const char *data, size_t len);
 mp_obj_t mp_obj_new_str_from_vstr(const mp_obj_type_t *type, vstr_t *vstr);
 mp_obj_t mp_obj_new_bytes(const byte *data, size_t len);
-mp_obj_t mp_obj_new_bytearray(size_t n, void *items);
+mp_obj_t mp_obj_new_bytearray(size_t n, const void *items);
 mp_obj_t mp_obj_new_bytearray_by_ref(size_t n, void *items);
 #if MICROPY_PY_BUILTINS_FLOAT
 mp_obj_t mp_obj_new_int_from_float(mp_float_t val);