linux-phytec-ti

soundwire: fix SPDX license for header files

Some more headers had C++ style SDPX line, fix that and change copyright
so that it is consistent with rest of the code in subsystem

Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>