patch 8.2.3356: adding many text properties requires a lot of function calls

Problem:    Adding many text properties requires a lot of function calls.
Solution:   Add the prop_add_list() function. (Yegappan Lakshmanan,
            closes #8751)
diff --git a/src/evalfunc.c b/src/evalfunc.c
index 2b50798..4d73d40 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -708,6 +708,7 @@
 static argcheck_T arg2_buffer_string[] = {arg_buffer, arg_string};
 static argcheck_T arg2_chan_or_job_dict[] = {arg_chan_or_job, arg_dict_any};
 static argcheck_T arg2_chan_or_job_string[] = {arg_chan_or_job, arg_string};
+static argcheck_T arg2_dict_any_list_any[] = {arg_dict_any, arg_list_any};
 static argcheck_T arg2_dict_any_string_or_nr[] = {arg_dict_any, arg_string_or_nr};
 static argcheck_T arg2_dict_string[] = {arg_dict_any, arg_string};
 static argcheck_T arg2_float_or_nr[] = {arg_float_or_nr, arg_float_or_nr};
@@ -1740,6 +1741,8 @@
 			ret_void,	    JOB_FUNC(f_prompt_setprompt)},
     {"prop_add",	3, 3, FEARG_1,	    arg3_number_number_dict,
 			ret_void,	    PROP_FUNC(f_prop_add)},
+    {"prop_add_list",	2, 2, FEARG_1,	    arg2_dict_any_list_any,
+			ret_void,	    PROP_FUNC(f_prop_add_list)},
     {"prop_clear",	1, 3, FEARG_1,	    arg3_number_number_dict,
 			ret_void,	    PROP_FUNC(f_prop_clear)},
     {"prop_find",	1, 2, FEARG_1,	    arg2_dict_string,