Clean up GnuTLS PKCS#12 handling a little
Clean up GnuTLS PKCS#12 handling a little

Also try other types if gnutls_pkcs12_verify_mac() returns anything other
than GNUTLS_E_MAC_VERIFY_FAILED.

Signed-off-by: David Woodhouse <b460d66aaf00c296a3db1c1d9eeafc081d5f7d70@intel.com>

neshema/openconnect,nmav/openconnect-mine,don-johnny/openconnect,atyndall/openconnect,lins05/openconnect,mtmiller/openconnect,mveplus/openconnect-client,matlockx/openconnect,liiir1985/openconnect,chadcatlett/openconnect,atyndall/openconnect,cernekee/openconnect,chadcatlett/openconnect,chadcatlett/openconnect,liiir1985/openconnect,brandt/openconnect,mveplus/openconnect-client,nmav/openconnect-mine,nmav/openconnect-mine,mveplus/openconnect-client,neshema/openconnect,neshema/openconnect,sihde/openconnect,lins05/openconnect,brandt/openconnect,matlockx/openconnect,sihde/openconnect,liiir1985/openconnect,don-johnny/openconnect,matlockx/openconnect,chadcatlett/openconnect,nmav/openconnect-mine,mveplus/openconnect-client,matlockx/openconnect,neshema/openconnect,don-johnny/openconnect,cernekee/openconnect,brandt/openconnect,mtmiller/openconnect,brandt/openconnect,cernekee/openconnect,cernekee/openconnect,certik/openconnect,liiir1985/openconnect,atyndall/openconnect,sihde/openconnect,atyndall/openconnect,don-johnny/openconnect,lins05/openconnect,certik/openconnect,mtmiller/openconnect,lins05/openconnect,mtmiller/openconnect,certik/openconnect