Uniformize STMicroelectronics copyrights header
Add SPDX identifier
Signed-off-by: NBenjamin Gaignard <benjamin.gaignard@st.com>
Acked-by: NAlexandre TORGUE <alexandre.torgue@st.com>
Acked-by: NMaxime Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>