replace lrint with lround

lrint is a configurable version of lround that behaves either as round,
floor, ceil, or trunc based on setting the proper FE_ macro using
fset/getround. Given that it's not set at all and that it defaults to
round behavior, simply replace with round.

Also removed the util/Math defines.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

src/util/Math.hxx

@@ -32,12 +32,9 @@
 
 #ifdef __UCLIBC__
 #include <boost/math/special_functions/round.hpp>
-using boost::math::iround;
 using boost::math::lround;
-#define lrint iround
 #else
 #include <cmath>
-using std::lrint;
 using std::lround;
 #endif