util/incore update that allows FINGERPRINT_premain-free build.

As for complementary fips.c modification. Goal is to ensure that
FIPS_signature does not end up in .bss segment, one guaranteed to
be zeroed upon program start-up. One would expect explicitly
initialized values to end up in .data segment, but it turned out
that values explicitly initialized with zeros can end up in .bss.
The modification does not affect program flow, because first byte
was the only one of significance [to FINGERPRINT_premain].

Reviewed-by: Dr. Stephen Henson <steve@openssl.org>