@hank-*-boost: reduced ripple on low modes

by raising MCU clock speed to half at levels 2+
instead of the previous value of 1/4th speed

I tried full speed too, which makes ripple much smaller and faster...
but it also causes a big jump in brightness between levels 1 and 2.
My lux meter shows ~350 at 1/150 or ~500 at 2/150,
but at half speed it's ~650 at 2/150,
and at full speed it's ~1100 at 2/150.
So I went for a happy medium to balance ripple, brightness, and runtime.

Author: ToyKeeper

hw/hank/noctigon-dm11/boost/anduril.h

@@ -31,10 +31,12 @@
 #define MIN_THERM_STEPDOWN 50
 #define DEFAULT_LEVEL 70
 #define MAX_1x7135 150
-// always run at 1/4th speed, because 4 kHz PWM is enough for this circuit
+// moon at 1/4th speed for max runtime
+// the rest at half speed, to reduce ripple
+// but not full speed because 8 kHz PWM is enough for this circuit
 // and speed changes make a big visible bump
 #define HALFSPEED_LEVEL     255
-#define QUARTERSPEED_LEVEL  255
+#define QUARTERSPEED_LEVEL  2
 
 #define RAMP_SMOOTH_FLOOR 1  // low levels may be unreliable
 #define RAMP_SMOOTH_CEIL  130

hw/hank/noctigon-k1/boost/anduril.h

@@ -41,10 +41,12 @@
 #define MIN_THERM_STEPDOWN 50
 #define DEFAULT_LEVEL 70
 #define MAX_1x7135 150
-// always run at 1/4th speed, because 4 kHz PWM is enough for this circuit
+// moon at 1/4th speed for max runtime
+// the rest at half speed, to reduce ripple
+// but not full speed because 8 kHz PWM is enough for this circuit
 // and speed changes make a big visible bump
 #define HALFSPEED_LEVEL     255
-#define QUARTERSPEED_LEVEL  255
+#define QUARTERSPEED_LEVEL  2
 
 #define RAMP_SMOOTH_FLOOR 1
 #define RAMP_SMOOTH_CEIL  130