usb: isp1760: remove SLAB_MEM_SPREAD flag usage

usb: isp1760: remove SLAB_MEM_SPREAD flag usage

The SLAB_MEM_SPREAD flag used to be implemented in SLAB, which was
removed as of v6.8-rc1, so it became a dead flag since the commit
16a1d968358a ("mm/slab: remove mm/slab.c and slab_def.h"). And the
series[1] went on to mark it obsolete explicitly to avoid confusion
for users. Here we can just remove all its users, which has no any
functional change.

[1] https://lore.kernel.org/all/20240223-slab-cleanup-flags-v2-1-02f1753e8303@suse.cz/

Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Acked-by: Rui Miguel Silva <rui.silva@linaro.org>
Link: https://lore.kernel.org/r/20240305132442.2122214-1-chengming.zhou@linux.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>