Remove some OPENSSL_NO_SHA that snuck in

Commit d064e6ab removed all the
OPENSSL_NO_SHA guards, but commit
a50ad1da

 regenerated some due to the
sha entries in the %md_disabler table in apps/progs.pl.

Update %md_disabler to reflect that sha is not disableable, and
remove OPENSSL_NO_SHA for good.

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>