clk: Drop unused COMMON_CLK_STM32MP157_SCMI config

clk: Drop unused COMMON_CLK_STM32MP157_SCMI config

Commit 21e743300dd0 ("clk: stm32mp1: new compatible for secure RCC support")
introduced a new Kconfig option COMMON_CLK_STM32MP157_SCMI which is not
used anywhere.

Further, it looks like this Kconfig option is just to select bunch of other
options which doesn't sound correct to me. There is no need for another
SCMI firmware based clock driver and hence the same applies for the config
option too.

Let us just drop the unused COMMON_CLK_STM32MP157_SCMI before it gives
someone idea to write a specific clock driver for this SoC/platform.

Cc: Etienne Carriere <etienne.carriere@foss.st.com>
Cc: Gabriel Fernandez <gabriel.fernandez@foss.st.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20211015150043.140793-1-sudeep.holla@arm.com
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>