PCI: pci-bridge-emul: Add PCIe Root Capabilities Register

stable inclusion
from stable-5.10.69
commit 9e766b86a9ef653a8ca48a9f70d3dbb580284594
bugzilla: 182675 https://gitee.com/openeuler/kernel/issues/I4I3ED

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=9e766b86a9ef653a8ca48a9f70d3dbb580284594

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commit e902bb7c upstream.

The 16-bit Root Capabilities register is at offset 0x1e in the PCIe
Capability. Rename current 'rsvd' struct member to 'rootcap'.

Link: https://lore.kernel.org/r/20210722144041.12661-4-pali@kernel.org


Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Acked-by: Weilong Chen <chenweilong@huawei.com>

Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>