function.xsl: Default values can not be annotated

doxygen/doxygen2boostbook.xsl: If the string "detail::" is found in a
type or default argument, the type/argument is replaced with
"unspecified".


[SVN r20810]

tools/boostbook

@@ -1 +1 @@
-Subproject commit 701f383881f21ea42c761e77a76e96f7a8ba40c8
+Subproject commit 02fd5d3611b921698f5c5e483a941c48b2374f09