clk: renesas: rcar-gen3: Rename rint to .r

All other internal clock names have a period prepended.

Hence rename the internal RCLK from "rint" to ".r", and move it to the
section where all other internal clocks are defined.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>