fix references inside IDA to `objc_msgSend` for ios16

fix_ios16_objc_msgSend_refs.py

import idc
import idautils
import ida_xref

# iterate over all objc_msgSend code references
objc_msgSend = idc.get_name_ea_simple('_objc_msgSend')
for xref in idautils.XrefsTo(objc_msgSend):
    if xref.type & ida_xref.XREF_DATA:
        continue

    # extract the selector name from the first opcode
    func_start_ea = idc.get_func_attr(xref.frm, idc.FUNCATTR_START)
    refs = list(idautils.DataRefsFrom(func_start_ea))

    if not refs:
        continue

    p_selector_ea = refs[0]
    selector_ea = list(idautils.DataRefsFrom(p_selector_ea))[0]
    string_type = idc.get_str_type(selector_ea)
    selector_str = idc.get_strlit_contents(selector_ea, strtype=string_type).decode()

    # name the function and set its type
    name = f'objc_msgSend_{selector_str.replace(":", "_")}'
    args = ['id object', 'SEL selector']
    if ':' in selector_str:
        for arg in selector_str.split(':'):
            if arg:
                args.append(f'id {arg}')
    type_ = f'int {name}({", ".join(args)})'
    print(f'0x{func_start_ea:x} {name} {type_}')
    idc.set_name(func_start_ea, name, idc.SN_CHECK)
    idc.SetType(func_start_ea, type_)