clocksource: marco: Rename marco to atlas7

marco project is replaced by atlas7 and we should obliterate
its all traces.

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>