clk: shmobile: Deprecate renesas,clock-indices

Commit 8e33f91a

 ("clk: shmobile: clk-mstp: change to using
clock-indices") forgot to replace all occurrences of
"renesas,clock-indices" in the driver-specific binding documentation.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>