modpost: restore the warning message for missing symbol versions

This log message was accidentally chopped off.

I was wondering why this happened, but checking the ML log, Mark
precisely followed my suggestion [1].

I just used "..." because I was too lazy to type the sentence fully.
Sorry for the confusion.

[1]: https://lore.kernel.org/all/CAK7LNAR6bXXk9-ZzZYpTqzFqdYbQsZHmiWspu27rtsFxvfRuVA@mail.gmail.com/

Fixes: 4a67959 ("kbuild: modpost: Explicitly warn about unprototyped symbols")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>

Author: masahir0y

scripts/mod/modpost.c

@@ -674,7 +674,7 @@ static void handle_modversion(const struct module *mod,
 	unsigned int crc;
 
 	if (sym->st_shndx == SHN_UNDEF) {
-		warn("EXPORT symbol \"%s\" [%s%s] version ...\n"
+		warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n"
 		     "Is \"%s\" prototyped in <asm/asm-prototypes.h>?\n",
 		     symname, mod->name, mod->is_vmlinux ? "" : ".ko",
 		     symname);