usb: host: remove unnecessary condition check

dma_pool_destroy() can handle NULL pointer correctly, so there is
no need to check NULL pointer before calling dma_pool_destroy().

Signed-off-by: Chengguang Xu <[e-mail]>
Acked-by: Alan Stern <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/host/ohci-mem.c

···
 
 static void ohci_mem_cleanup (struct ohci_hcd *ohci)
 {
-	if (ohci->td_cache) {
-		dma_pool_destroy (ohci->td_cache);
-		ohci->td_cache = NULL;
-	}
-	if (ohci->ed_cache) {
-		dma_pool_destroy (ohci->ed_cache);
-		ohci->ed_cache = NULL;
-	}
+	dma_pool_destroy(ohci->td_cache);
+	ohci->td_cache = NULL;
+	dma_pool_destroy(ohci->ed_cache);
+	ohci->ed_cache = NULL;
 }
 
 /*-------------------------------------------------------------------------*/