clocksource: em_sti: convert to clk_prepare/unprepare
clocksource: em_sti: convert to clk_prepare/unprepare

Add calls to clk_prepare and unprepare so that EMMA Mobile EV2 can
migrate to the common clock framework.

Signed-off-by: Shinya Kuribayashi <039822ba0520bbe58ce7503b63b474f64f04ae3a@renesas.com>
Acked-by: Daniel Lezcano <e9fa45941f2ebe89c1b9d6c5f339ab42eadb8567@linaro.org>
Acked-by: Laurent Pinchart <3ded2f39a78f0d7044839546f95841842b4d7c96@ideasonboard.com>
Acked-by: Magnus Damm <2336f5729424d0c84d319e991b3648cafa2c3c5b@opensource.se>
Signed-off-by: Simon Horman <9662bddcc379be37df16f02a449c344b4718c1a1@verge.net.au>
Signed-off-by: Daniel Lezcano <e9fa45941f2ebe89c1b9d6c5f339ab42eadb8567@linaro.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs