phase2-auth applies for EAP-TTLS and EAP-PEAP but the interpretation is
different for one than for the other, clarify the difference.
phase2-auth is for the non-EAP inner methods of EAP-TTLS but is also for
the EAP inner methods of EAP-PEAP. EAP-PEAP doesn't use phase2-autheap
and doesn't support any non-EAP methods.
Given how complicated EAP configuration is it's likely that people just
use example configurations rather than look at the docs. The example
configuration in man/nm-settings-keyfile.xsl is correct in using PEAP
together with phase2-auth=mschapv2.
[thaller@redhat.com: regenerate documentation files]
ba7a13789f