KNF.

I just spent too long chasing a bug in here and really should have done
this first. Gem of the day... is it an if test or a for loop? No, it is a
super ifloop!

if (!(flags & PKCS7_NOVERIFY)) for (k = 0; k < sk_X509_num(signers); k++) {
Fix file descriptor leak

(Thanks to Brent Cook)

OK from jsing@
Free "data" when it's no longer in use.

(Thanks to Brent Cook)

OK from jsing@