[Mesa-dev] No more make clean!

[Eric Anholt]

It still has the flaw that changes to source lists and Makefile.ams
don't rebuild Makefile as often as they should.  This is because our
top-level Makefile isn't in automake, and has just a stub am-refresh
target.  I have a series to convert that, but it means getting rid of
the static configs.  I'd love to see them die (they're just a trap
these days), but I'll wait on that for another patchbomb.

I also want libglsl.so to get merged into libdricore.so, and to make
libdricore sit in a normal lib directory without rpath.  That's next
on my list.