qemu: gpu: Sanitize error values in qemuVhostUserGPUGetPid

The caller doesn't care about the actual return value, so return -1
rather than errno.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

src/qemu/qemu_vhost_user_gpu.c

@@ -61,7 +61,7 @@ qemuVhostUserGPUCreatePidFilename(const char *stateDir,
  * @alias: video device alias
  * @pid: pointer to pid
  *
- * Return -errno upon error, or zero on successful reading of the pidfile.
+ * Return -1 upon error, or zero on successful reading of the pidfile.
  * If the PID was not still alive, zero will be returned, and @pid will be
  * set to -1;
  */
@@ -74,11 +74,13 @@ qemuVhostUserGPUGetPid(const char *binPath,
 {
     g_autofree char *pidfile = NULL;
 
-    pidfile = qemuVhostUserGPUCreatePidFilename(stateDir, shortName, alias);
-    if (!pidfile)
-        return -ENOMEM;
+    if (!(pidfile = qemuVhostUserGPUCreatePidFilename(stateDir, shortName, alias)))
+        return -1;
+
+    if (virPidFileReadPathIfAlive(pidfile, pid, binPath) < 0)
+        return -1;
 
-    return virPidFileReadPathIfAlive(pidfile, pid, binPath);
+    return 0;
 }