properties: allow choosing certificate from a PKCS#11 token
Apparently, openconnect can handle certificates from PKCS#11 tokens. Drop the NMA_CERT_CHOOSER_FLAG_PEM flags from NmaCertChoosers.
Apparently, openconnect can handle certificates from PKCS#11 tokens. Drop the NMA_CERT_CHOOSER_FLAG_PEM flags from NmaCertChoosers.