xhci: mem: Use dma_poll_zalloc() instead of explicit memset()

Use dma_poll_zalloc() instead of explicit memset() call in
xhci_alloc_stream_ctx(). Note, that dma_alloc_coherent() is
always issues zeroed memory chunk.

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/20230317154715.535523-3-mathias.nyman@linux.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>