USB: xhci: fix couple sparse annotations

There is no point in casting to (void *) when setting up xhci->ir_set
as it only makes us lose __iomem annotation and makes sparse unhappy.

OTOH we do need to cast to (void *) when calculating xhci->dba from
offset, but since it is IO memory we need to annotate it as such.
Signed-off-by: Dmitry Torokhov <dtor@vmware.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>

drivers/usb/host/xhci-mem.c

@@ -1900,11 +1900,11 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 	val &= DBOFF_MASK;
 	xhci_dbg(xhci, "// Doorbell array is located at offset 0x%x"
 			" from cap regs base addr\n", val);
-	xhci->dba = (void *) xhci->cap_regs + val;
+	xhci->dba = (void __iomem *) xhci->cap_regs + val;
 	xhci_dbg_regs(xhci);
 	xhci_print_run_regs(xhci);
 	/* Set ir_set to interrupt register set 0 */
-	xhci->ir_set = (void *) xhci->run_regs->ir_set;
+	xhci->ir_set = &xhci->run_regs->ir_set[0];
 
 	/*
 	 * Event ring setup: Allocate a normal ring, but also setup