Go ahead and exempt selected profile-specific USE_EXPAND

Go ahead and exempt selected profile-specific USE_EXPAND
flags from IUSE QA Notices since we are planning to make
these particular flags into implicit members of IUSE.
We can make this extensible later, but for now we just
want to eliminate some useless QA Notices (a subset of
bug #70648). We're not exempting any non profile-
specific USE_EXPAND flags here. For non profile-specific
flags, we intend to implement an IUSE syntax extension
(bug #133327). (trunk r8442)

svn path=/main/branches/2.1.2/; revision=8443