clk: scmi: Defer issue of SCMI_CLOCK_ATTRIBUTES

clk: scmi: Defer issue of SCMI_CLOCK_ATTRIBUTES

Instead of resolving clock control flags using SCMI_CLOCK_ATTRIBUTES
during probe for each and every clock, resolve the clock control
flags using SCMI_CLOCK_ATTRIBUTES when the clock control flags are
first used. Because most clock are never used by U-Boot, this allows
reducing the amount of SCMI_CLOCK_ATTRIBUTES considerably, and this
improve probe time of the scmi clock driver and U-Boot start up time.

On Renesas X5H, with 1700+ SCMI clock, the boot time improved by 1.7s .

Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Signed-off-by: Peng Fan <peng.fan@nxp.com>