patch 8.2.4825: can only get a list of mappings

Problem:    Can only get a list of mappings.
Solution:   Add the optional {abbr} argument. (Ernie Rael, closes #10277)
            Rename to maplist().  Rename test file.
diff --git a/src/evalfunc.c b/src/evalfunc.c
index 090f3a7..86a7c0d 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -1871,8 +1871,6 @@
 			ret_getline,	    f_getline},
     {"getloclist",	1, 2, 0,	    arg2_number_dict_any,
 			ret_list_or_dict_1, f_getloclist},
-    {"getmappings",		0, 0, 0,	    NULL,
-			ret_list_dict_any,  f_getmappings},
     {"getmarklist",	0, 1, FEARG_1,	    arg1_buffer,
 			ret_list_dict_any,  f_getmarklist},
     {"getmatches",	0, 1, 0,	    arg1_number,
@@ -2049,6 +2047,8 @@
 			ret_maparg,	    f_maparg},
     {"mapcheck",	1, 3, FEARG_1,	    arg3_string_string_bool,
 			ret_string,	    f_mapcheck},
+    {"maplist",		0, 1, 0,	    arg1_bool,
+			ret_list_dict_any,  f_maplist},
     {"mapnew",		2, 2, FEARG_1,	    arg2_mapnew,
 			ret_first_cont,	    f_mapnew},
     {"mapset",		3, 3, FEARG_1,	    arg3_string_bool_dict,