qemu: capabilities: Tolerate missing @qemuCaps in virQEMUCapsSupportsGICVersion

Report the given GIC version as unsupported if @qemuCapsi is NULL. This
will be helpful to run post parse callbacks even if qemu is not
currently installed.

src/qemu/qemu_capabilities.c

@@ -5676,7 +5676,8 @@ virQEMUCapsFillDomainDeviceHostdevCaps(virQEMUCapsPtr qemuCaps,
  * @version: GIC version
  *
  * Checks the QEMU binary with capabilities @qemuCaps supports a specific
- * GIC version for a domain of type @virtType.
+ * GIC version for a domain of type @virtType. If @qemuCaps is NULL, the GIC
+ * @version is considered unsupported.
  *
  * Returns: true if the binary supports the requested GIC version, false
  *          otherwise
@@ -5688,6 +5689,9 @@ virQEMUCapsSupportsGICVersion(virQEMUCapsPtr qemuCaps,
 {
     size_t i;
 
+    if (!qemuCaps)
+        return false;
+
     for (i = 0; i < qemuCaps->ngicCapabilities; i++) {
         virGICCapabilityPtr cap = &(qemuCaps->gicCapabilities[i]);