[4/6] secur32: Return PRF algorithm value when using GCM. (resend)

[Michael Müller]

This patch broke the compilation on Debian Wheezy and Ubuntu Trusty:

schannel_gnutls.c: In function schannel_get_mac_algid:
schannel_gnutls.c:329:10: error: ‘GNUTLS_MAC_AEAD undeclared (first use in this function)
schannel_gnutls.c:329:10: note: each undeclared identifier is reported only once for each function it appears in

Build overview: https://dev.wine-staging.com/builder/group/60/ (Click Downloads for build logs)
Debian Wheezy build log: https://builds.wine-staging.com/2017-04-27-21-23-02-job-10597/build.log

Regards,
Michael