build: only run fdstreamtest when libvirtd is built

An rpm build with client_only set to 1 (for example, RHEL 5 on
s390, or by modifying libvirt.spec.in) failed with

TEST: fdstreamtest
 1) Stream read blocking                                              ... OK
 2) Stream read non-blocking                                          ... Unexpected EOF block 0 want 128
FAILED
 3) Stream write blocking                                             ... OK
 4) Stream write non-blocking                                         ... Failed to finish stream: internal error: libvirt:  error : cannot execute binary /home/eblake/rpmbuild/BUILD/libvirt-1.1.1/tests/../src/libvirt_iohelper: No such file or directory

Since the test depends on something that was only built for
WITH_LIBVIRTD (see src/Makefile.am), we must do the same for
the test.

* tests/Makefile.am (test_programs): Make fdstreamtest conditional.
Signed-off-by: NEric Blake <eblake@redhat.com>

tests/Makefile.am

@@ -128,10 +128,13 @@ test_programs = virshtest sockettest \
         virportallocatortest \
 	sysinfotest \
 	virstoragetest \
-        fdstreamtest \
         fchosttest \
 	$(NULL)
 
+if WITH_LIBVIRTD
+test_programs += fdstreamtest
+endif WITH_LIBVIRTD
+
 if WITH_DBUS
 test_programs += virdbustest \
                  virsystemdtest