clk(4): clk_set_rate: Add KASSERT to check `clk != NULL`

branches: 1.7.28;
Normalize clk name to prevent sysctl_createv from failing

Make "put" clk func optional

branches: 1.5.2;
If setting rate on a clock with no set_rate function, and the desired rate
matches the current rate, don't return an error.

Create private sysctl nodes for inspecting clock trees.

As discussed on tech-kern@ 10 days ago, add a clk_round_rate() method,
which returns the rate that would be used by this clock if clk_set_rate()
was called. Used by drivers (or other clocks) which have their own divider
and need to know the parent's clock capabilities to compute the best
parameters.

branches: 1.2.10; 1.2.12;
Add support for multiple clock domains in clk API.

branches: 1.1.2; 1.1.4; 1.1.6;
Add basic clock device infrastructure.

As discussed on tech-kern@ 10 days ago, add a clk_round_rate() method,
which returns the rate that would be used by this clock if clk_set_rate()
was called. Used by drivers (or other clocks) which have their own divider
and need to know the parent's clock capabilities to compute the best
parameters.

branches: 1.2.10; 1.2.12;
Add support for multiple clock domains in clk API.

branches: 1.1.2; 1.1.4; 1.1.6;
Add basic clock device infrastructure.

Create private sysctl nodes for inspecting clock trees.

As discussed on tech-kern@ 10 days ago, add a clk_round_rate() method,
which returns the rate that would be used by this clock if clk_set_rate()
was called. Used by drivers (or other clocks) which have their own divider
and need to know the parent's clock capabilities to compute the best
parameters.

branches: 1.2.10; 1.2.12;
Add support for multiple clock domains in clk API.

branches: 1.1.2; 1.1.4; 1.1.6;
Add basic clock device infrastructure.

branches: 1.1.2; 1.1.18;
Add basic clock device infrastructure.