Remove dependencies on Boost.StaticAssert.

Boost.StaticAssert has been merged into Boost.Config, so remove
the dependency.

Author: Lastique

CMakeLists.txt

@@ -94,7 +94,6 @@ target_link_libraries(boost_iostreams
     Boost::range
     Boost::regex
     Boost::smart_ptr
-    Boost::static_assert
     Boost::throw_exception
     Boost::type_traits
     Boost::utility

build.jam

@@ -22,7 +22,6 @@ constant boost_dependencies :
     /boost/range//boost_range
     /boost/regex//boost_regex
     /boost/smart_ptr//boost_smart_ptr
-    /boost/static_assert//boost_static_assert
     /boost/throw_exception//boost_throw_exception
     /boost/type_traits//boost_type_traits
     /boost/utility//boost_utility ;