Since 30b5707c (qom: Remove module_obj_name parameter from
OBJECT_DECLARE* macros) we don't need the additional two parameters.
Fix the documentation.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220725140520.515340-13-alex.bennee@linaro.org>