Fix two bugs:

Fix two bugs:
1. Nothing should happen on "make all". Doc generation is quick, but we
   don't want to do it unless we're installing.
2. Correct a dependency for the *.ps files .. didn't notice this before
   because of cruft in my directory. It failed on a clean build.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@18359 91177308-0d34-0410-b5e6-96231b3b80d8