Talking to fluffy@ on IRC, I found out the hard way that my commit
0ba35fd5a81df57fb0f943c3dddd35d43ebc3383 has not been included in Qt
4.8.2, so things were pretty much borked when one tried to use
non-base gcc.
Instead of changing the behavior of g++-base.conf and setting
QMAKE_{CC,CXX} in "leaf" mkspecs, my upstream commit simply sets these
values after including g++-base.conf where needed (ie. in the
freebsd-g++46 mkspec, where we use gcc46 and g++46).
Bump PORTREVISION once again, sorry for the hassle.
bc010169fe