vim-patch:partial:8.1.1981: the evalfunc.c file is too big (#24490)

Problem:    The evalfunc.c file is too big.
Solution:   Move undo functions to undo.c.  Move cmdline functions to
            ex_getln.c.  Move some container functions to list.c.

08c308aeb5

Undo functions only. Cmdline functions have already been moved.
A lot of container functions have been added to eval/funcs.c instead of
list.c in previously ported Vim 8.2.x patches, so deal with that later.

Co-authored-by: Bram Moolenaar <Bram@vim.org>

src/nvim/generators/gen_eval.lua

@@ -39,6 +39,7 @@ hashpipe:write([[
 #include "nvim/strings.h"
 #include "nvim/sign.h"
 #include "nvim/testing.h"
+#include "nvim/undo.h"
 
 ]])