thermal: cpu_cooling: update copyright tags

Adding my copyright information for two purposes:
- To get cc'd for future patches to review (Only if people read this header
  while sending mail)
- Have done enough changes to earn a place here?

Cc: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
(cherry picked from commit 73904cbc1a5a5143323743209257d4668fadc7f3)
Signed-off-by: Kevin Hilman <khilman@linaro.org>