interconnect: Move internal structs into a separate file

[ Upstream commit dd018a9cf9108f9c7d924f6fe09aed745e78a67e ]

Move the interconnect framework internal structs into a separate file,
so that it can be included and used by ftrace code. This will allow us
to expose some more useful information in the traces.

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
Stable-dep-of: d2d69354226d ("USB: dwc3: qcom: fix NULL-deref on suspend")
Signed-off-by: Sasha Levin <sashal@kernel.org>