xhci: Show Zhaoxin XHCI root hub speed correctly

zhaoxin inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I40QDN


CVE: NA

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Some Zhaoxin xHCI controllers follow usb3.1 spec,
but only support gen1 speed 5G. While in Linux kernel,
if xHCI suspport usb3.1,root hub speed will show on 10G.
To fix this issue, read usb speed ID supported by xHCI
to determine root hub speed.

Signed-off-by: LeoLiu-oc <LeoLiu-oc@zhaoxin.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>