As the board on the GW1N-1 chip becomes a rarity, its replacement is the
Tangnano1k board with the GW1NZ-1 chip. This chip has a unique mechanism
for turning off power to important things such as OSC, PLL, etc.
Here we introduce a primitive that allows energy saving to be controlled
dynamically.
We also bring the names of some functions to uniformity.
Signed-off-by: YRabbit <rabbit@yrabbit.cyou>