Adjust boostbook test for boostbook changes. It

seems that doxygen target now produces a target
with different name, and it does not produce
any target unless there's explicit dependency
on it. I'm not sure I like the change, but
anyway.


[SVN r39605]

tools/build

@@ -1 +1 @@
-Subproject commit 411e5f6d406f3ec2222d6f3843ebcafd15e548f8
+Subproject commit 8b00e3a41eac9e294c5d751d0dffc1ea956535ec