Make it build on openbsd.

Build on amd64 and sparc64.

configure.ac

@@ -50,6 +50,7 @@ case $host_os in
   ;;
   *openbsd*)
     bsd=true
+    openbsd=true
     AC_DEFINE(HAVE_OPENBSD, 1, [OpenBSD])
   ;;
   *netbsd*)
@@ -133,6 +134,7 @@ AC_ARG_WITH(windows2000,
 
 AM_CONDITIONAL(LINUX, test "$linux" = true)
 AM_CONDITIONAL(BSD, test "$bsd" = true)
+AM_CONDITIONAL(OPENBSD, test "$openbsd" = true)
 AM_CONDITIONAL(DARWIN, test "$darwin" = true)
 AM_CONDITIONAL(SOLARIS, test "$solaris" = true)
 AM_CONDITIONAL(MINGW, test "$mingw" = true)

src/Makefile.am

@@ -191,10 +191,12 @@ sptps_test_LDADD = libtincd.la libed25519.la libtincconf.la libchacha_poly1305.l
 sptps_keypair_LDADD = libed25519.la libtincconf.la libchacha_poly1305.la libtincd.la libchacha_poly1305.la
 
 if !DARWIN
+if !OPENBSD
 sptps_speed_LDADD += -lrt
 sptps_test_LDADD += -lrt
 sptps_keypair_LDADD += -lrt
 endif
+endif
 
 LIBS = @LIBS@ -lm