interconnect: icc-clk: fix modular build

Fix building interconnect-clk as a module:
- Add EXPORT_SYMBOL_GPL to the exported functions
- Add MODULE_DESCRIPTION/_LICENSE/_AUTHOR

Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20230519230122.3958816-1-dmitry.baryshkov@linaro.org


Signed-off-by: Georgi Djakov <djakov@kernel.org>