firmware: arm_scmi: Fix transport device teardown lookup

In the Linux kernel, the following vulnerability has been resolved:

firmware: arm_scmi: Fix transport device teardown lookup

SCMI transport devices are deliberately excluded from normal SCMI bus
matching so protocol drivers cannot bind to the internal transport
children. However, scmi_device_destroy() uses the same protocol/name
lookup to find devices that must be unregistered during channel teardown.

Split the match helper so driver matching still skips transport devices,
while explicit child lookup can find them for teardown. Use a shared
transport-device name prefix macro for both matching and name generation.

Since transport-device names are derived from direction and protocol ID,
reject duplicate protocol channel setup before creating or finding a
transport device. This prevents malformed firmware with duplicate
protocol child nodes from reusing an existing transport device and then
destroying it when the duplicate IDR insertion fails.