vim-patch:8.2.1909: number of status line items is limited to 80

Problem:    Number of status line items is limited to 80.
Solution:   Dynamically allocate the arrays. (Rom Grk, closes vim/vim#7181)
8133cc6bf4

The members of stl_item_T have not been prefixed with stl_ contrary to
the vim patch because the amount of stl_ prefixes on single lines of
code in that region was hurtful to readability.

src/nvim/vim.h

@@ -259,7 +259,6 @@ enum { FOLD_TEXT_LEN = 51 };  //!< buffer size for get_foldtext()
 #define PERROR(msg) (void) emsgf("%s: %s", msg, strerror(errno))
 
 #define SHOWCMD_COLS 10                 // columns needed by shown command
-#define STL_MAX_ITEM 80                 // max nr of %<flag> in statusline
 
 #include "nvim/path.h"