VDSO_SYMBOL_MAX is max number of symbols, not their max length.
Fixes my buggy commit: 4c69339c ("string.h/pie: use builtin strncmp
instead of strcmp"). Sorry for that bogus misprinting.

Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>