clk: stm32: Fix ltdc's clock turn off by clk_disable_unused() after system enter shell

stm32's clk driver register two ltdc gate clk to clk core by
clk_hw_register_gate() and clk_hw_register_composite()

first: 'stm32f429_gates[]', clk name is 'ltdc', which no user to use.
second: 'stm32f429_aux_clk[]', clk name is 'lcd-tft', used by ltdc driver

both of them point to the same offset of stm32's RCC register. after
kernel enter console, clk core turn off ltdc's clk as 'stm32f429_gates[]'
is no one to use. but, actually 'stm32f429_aux_clk[]' is in use.

stm32f469/746/769 have the same issue, fix it.

Fixes: daf2d117 ("clk: stm32f4: Add lcd-tft clock")
Link: https://lore.kernel.org/linux-arm-kernel/1590564453-24499-7-git-send-email-dillon.minfei@gmail.com/
Link: https://lore.kernel.org/lkml/CAPTRvHkf0cK_4ZidM17rPo99gWDmxgqFt4CDUjqFFwkOeQeFDg@mail.gmail.com/


Signed-off-by: Dillon Min <dillon.minfei@gmail.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Acked-by: Gabriel Fernandez <gabriel.fernandez@foss.st.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/1635232282-3992-10-git-send-email-dillon.minfei@gmail.com


Signed-off-by: Stephen Boyd <sboyd@kernel.org>