look for getloadavg.c in $topdir/lib, not $srcdir/lib

git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@613 f882894a-f735-0410-b71e-b25c423dba1c

configure.in

@@ -27,7 +27,7 @@ AC_MINIX
 AC_PROG_MAKE_SET
 AC_PROG_AWK
 
-AC_FUNC_GETLOADAVG($srcdir/lib)
+AC_FUNC_GETLOADAVG($topdir/lib)
 
 ifdef([AC_FUNC_STRTOD],[AC_FUNC_STRTOD],[AM_FUNC_STRTOD])
 dnl AM_WITH_REGEX