[PATCH v2] clk: meson: use SPDX license identifiers consistently

[Stephen Boyd]

Quoting Jerome Brunet (2018-05-16 01:50:40)
> Replace every license notices in drivers/clk/meson by SPDX license
> identifiers, as described in license-rules.rst
> 
> Acked-by: Neil Armstrong <narmstrong at baylibre.com>
> Signed-off-by: Jerome Brunet <jbrunet at baylibre.com>
> ---

Acked-by: Stephen Boyd <sboyd at kernel.org>

I take it this will come through a PR? Otherwise I can apply it to
clk-meson branch.