errors: Introduce "E856: Filename too long"

src/nvim/file_search.c

@@ -191,6 +191,8 @@ typedef struct ff_search_ctx_T {
 # include "file_search.c.generated.h"
 #endif
 
+static char_u e_pathtoolong[] = N_("E854: path too long for completion");
+
 /*
  * Initialization routine for vim_findfile().
  *