xhci: fix incorrect type in assignment in xhci_count_num_new_endpoints()

The fields 'add_flags' and 'drop_flags' in struct xhci_input_control_ctx
have type __le32 and need to be converted to CPU byteorder before being
used to derive the number of added endpoints.
This bug was found using sparse.

This patch is not suitable for stable, since the bug would only be
triggered on big endian systems, and the code only runs for Intel xHCI
host controllers, which are always integrated into little endian
systems.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

drivers/usb/host/xhci.c

@@ -1892,8 +1892,8 @@ static u32 xhci_count_num_new_endpoints(struct xhci_hcd *xhci,
 	 * (bit 1).  The default control endpoint is added during the Address
 	 * Device command and is never removed until the slot is disabled.
 	 */
-	valid_add_flags = ctrl_ctx->add_flags >> 2;
-	valid_drop_flags = ctrl_ctx->drop_flags >> 2;
+	valid_add_flags = le32_to_cpu(ctrl_ctx->add_flags) >> 2;
+	valid_drop_flags = le32_to_cpu(ctrl_ctx->drop_flags) >> 2;
 
 	/* Use hweight32 to count the number of ones in the add flags, or
 	 * number of endpoints added.  Don't count endpoints that are changed