refactor!: make unsued util functions private

If any public function is not used by any configuration, then we can
simply make them private. It is possible that there are external uses of
these functions, but a preliminary search indicated that usage is small
to non-existent.

Functions that are privatized:
- get_active_clients_list_by_ft

Work on neovim#2079.

lua/lspconfig/util.lua

@@ -208,7 +208,7 @@ function M.insert_package_json(config_files, field, fname)
   return config_files
 end
 
-function M.get_active_clients_list_by_ft(filetype)
+local function get_active_clients_list_by_ft(filetype)
   local clients = M.get_lsp_clients()
   local clients_list = {}
   for _, client in pairs(clients) do
@@ -225,7 +225,7 @@ end
 
 function M.get_other_matching_providers(filetype)
   local configs = require 'lspconfig.configs'
-  local active_clients_list = M.get_active_clients_list_by_ft(filetype)
+  local active_clients_list = get_active_clients_list_by_ft(filetype)
   local other_matching_configs = {}
   for _, config in pairs(configs) do
     if not vim.tbl_contains(active_clients_list, config.name) then
@@ -240,20 +240,6 @@ function M.get_other_matching_providers(filetype)
   return other_matching_configs
 end
 
-function M.get_config_by_ft(filetype)
-  local configs = require 'lspconfig.configs'
-  local matching_configs = {}
-  for _, config in pairs(configs) do
-    local filetypes = config.filetypes or {}
-    for _, ft in pairs(filetypes) do
-      if ft == filetype then
-        table.insert(matching_configs, config)
-      end
-    end
-  end
-  return matching_configs
-end
-
 function M.get_active_client_by_name(bufnr, servername)
   --TODO(glepnir): remove this for loop when we want only support 0.10+
   for _, client in pairs(M.get_lsp_clients { bufnr = bufnr }) do

plugin/lspconfig.lua

@@ -63,6 +63,21 @@ local get_clients_from_cmd_args = function(arg)
   return result
 end
 
+local function get_config_by_ft(filetype)
+  local configs = require 'lspconfig.configs'
+  local matching_configs = {}
+  for _, config in pairs(configs) do
+    local filetypes = config.filetypes or {}
+    for _, ft in pairs(filetypes) do
+      if ft == filetype then
+        table.insert(matching_configs, config)
+      end
+    end
+  end
+  return matching_configs
+end
+
+
 -- Called from plugin/lspconfig.vim because it requires knowing that the last
 -- script in scriptnames to be executed is lspconfig.
 api.nvim_create_user_command('LspInfo', ':che lspconfig', { desc = 'Deprecated alias to `:che lspconfig`' })
@@ -77,7 +92,7 @@ api.nvim_create_user_command('LspStart', function(info)
     end
   end
 
-  local matching_configs = util.get_config_by_ft(vim.bo.filetype)
+  local matching_configs = get_config_by_ft(vim.bo.filetype)
   for _, config in ipairs(matching_configs) do
     config.launch()
   end