qemuBuildNumaArgStr: Switch order of if() and for()

When building -numa command line there is a for() loop that
builds '-numa memdev=' for each guest NUMA node. And also
records in a local variable whether any of memory-object-*
backends must be used to satisfy desired config. Well, instead of
checking in each iteration whether corresponding capabilities are
set, we can do swap if() and for() and check only once.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

src/qemu/qemu_command.c

@@ -7043,11 +7043,11 @@ qemuBuildNumaArgStr(virQEMUDriverConfigPtr cfg,
 
     /* using of -numa memdev= cannot be combined with -numa mem=, thus we
      * need to check which approach to use */
-    for (i = 0; i < ncells; i++) {
     if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_RAM) ||
         virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_FILE) ||
         virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_MEMFD)) {
 
+        for (i = 0; i < ncells; i++) {
             if ((rc = qemuBuildMemoryCellBackendStr(def, cfg, i, priv,
                                                     &nodeBackends[i])) < 0)
                 goto cleanup;