vim-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 vim/vim#10277)
            Rename to maplist().  Rename test file.

09661203ec

Co-authored-by: Ernie Rael <errael@raelity.com>

src/nvim/eval.lua

@@ -3957,22 +3957,6 @@ M.funcs = {
     params = { { 'nr', 'integer' }, { 'what', 'any' } },
     signature = 'getloclist({nr} [, {what}])',
   },
-  getmappings = {
-    args = 0,
-    desc = [[
-      Returns a |List| of all mappings.  Each List item is a |Dict|,
-      the same as what is returned by |maparg()|, see
-      |mapping-dict|.
-
-      Example to show all mappings with "MultiMatch" in rhs: >
-      	echo getmappings()->filter({_, m ->
-      		\ match(get(m, 'rhs', ''), 'MultiMatch') >= 0
-      		\ })
-    ]],
-    name = 'getmappings',
-    params = {},
-    signature = 'getmappings()'
-  },
   getmarklist = {
     args = { 0, 1 },
     base = 1,
@@ -6158,7 +6142,8 @@ M.funcs = {
       When {dict} is omitted or zero: Return the rhs of mapping
       {name} in mode {mode}.  The returned String has special
       characters translated like in the output of the ":map" command
-      listing.
+      listing. When {dict} is TRUE a dictionary is returned, see
+      below. To get a list of all mappings see |maplist()|.
 
       When there is no mapping for {name}, an empty String is
       returned if {dict} is FALSE, otherwise returns an empty Dict.
@@ -6271,6 +6256,23 @@ M.funcs = {
     params = { { 'name', 'string' }, { 'mode', 'string' }, { 'abbr', 'any' } },
     signature = 'mapcheck({name} [, {mode} [, {abbr}]])',
   },
+  maplist = {
+    args = { 0, 1 },
+    desc = [[
+      Returns a |List| of all mappings.  Each List item is a |Dict|,
+      the same as what is returned by |maparg()|, see
+      |mapping-dict|.  When {abbr} is there and it is |TRUE| use
+      abbreviations instead of mappings.
+
+      Example to show all mappings with "MultiMatch" in rhs: >vim
+      	echo maplist()->filter({_, m ->
+      		\ match(get(m, 'rhs', ''), 'MultiMatch') >= 0
+      		\ })
+    ]],
+    name = 'maplist',
+    params = {},
+    signature = 'maplist([{abbr}])'
+  },
   mapnew = {
     args = 2,
     base = 1,