clk: Add hardware-enable column to clk summary

clk: Add hardware-enable column to clk summary

Add "hardware enable" column to the clk summary in order to show actual
hardware enable-state of all clocks. The possible states are "Y/N/?",
where question mark means that state is unknown, i.e. clock isn't a
mux and clk-driver doesn't support is_enabled() callback for this clock.

In conjunction with clk_ignore_unused, this tells us what unused clocks
are left enabled after bootloader. This is also a useful aid for
debugging interactions with firmware which changes clock states without
notifying kernel.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20201115203432.13934-1-digetx@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>