xhci: dbc: Drop duplicate checks for dma_free_coherent()

dma_free_coherent() is NULL-aware, not necessary to check for
the parameter twice. Drop duplicate conditionals in the caller.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20231201150647.1307406-2-mathias.nyman@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/xhci-dbgcap.c

@@ -28,7 +28,7 @@ static void dbc_ring_free(struct device *dev, struct xhci_ring *ring)
 	if (!ring)
 		return;
 
-	if (ring->first_seg && ring->first_seg->trbs) {
+	if (ring->first_seg) {
 		dma_free_coherent(dev, TRB_SEGMENT_SIZE,
 				  ring->first_seg->trbs,
 				  ring->first_seg->dma);
@@ -394,9 +394,8 @@ static int dbc_erst_alloc(struct device *dev, struct xhci_ring *evt_ring,
 
 static void dbc_erst_free(struct device *dev, struct xhci_erst *erst)
 {
-	if (erst->entries)
-		dma_free_coherent(dev, sizeof(struct xhci_erst_entry),
-				  erst->entries, erst->erst_dma_addr);
+	dma_free_coherent(dev, sizeof(struct xhci_erst_entry), erst->entries,
+			  erst->erst_dma_addr);
 	erst->entries = NULL;
 }
 
@@ -543,11 +542,8 @@ static void xhci_dbc_mem_cleanup(struct xhci_dbc *dbc)
 
 	xhci_dbc_eps_exit(dbc);
 
-	if (dbc->string) {
-		dma_free_coherent(dbc->dev, dbc->string_size,
-				  dbc->string, dbc->string_dma);
+	dma_free_coherent(dbc->dev, dbc->string_size, dbc->string, dbc->string_dma);
 	dbc->string = NULL;
-	}
 
 	dbc_free_ctx(dbc->dev, dbc->ctx);
 	dbc->ctx = NULL;