restore gamma correction on Model 100

This reverts commit 1d8eb6d2e2.

Rainbow effects on the Model 100 had some harsh transitions,
especially from red/orange to yellow.

@obra reported that the gamma implementation was disabled on the
Model 100 earlier because it broke the firmware so badly that
the keyboard was unusable for typing. This no longer seems to be
the case, possibly due to changes in the Arduino core and/or
<pgmspace.h> compatibility.

Signed-off-by: Taylor Yu <tlyu@mit.edu>

plugins/Kaleidoscope-Hardware-Keyboardio-Model100/src/kaleidoscope/driver/keyboardio/Model100Side.cpp

@@ -214,6 +214,7 @@ void Model100Side::sendLEDData() {
   }
 }
 
+auto constexpr gamma8 = kaleidoscope::driver::color::gamma_correction;
 
 void Model100Side::sendLEDBank(uint8_t bank) {
   uint8_t data[LED_BYTES_PER_BANK + 1];
@@ -229,25 +230,25 @@ void Model100Side::sendLEDBank(uint8_t bank) {
     else
       c = 0;
 
-    data[i + 1] = c;
+    data[i + 1] = pgm_read_byte(&gamma8[c]);
   }
   uint8_t result = writeData(data, ELEMENTS(data));
 }
 
 void Model100Side::setAllLEDsTo(cRGB color) {
   uint8_t data[] = {TWI_CMD_LED_SET_ALL_TO,
-                    color.b,
-                    color.g,
-                    color.r};
+                    pgm_read_byte(&gamma8[color.b]),
+                    pgm_read_byte(&gamma8[color.g]),
+                    pgm_read_byte(&gamma8[color.r])};
   uint8_t result = writeData(data, ELEMENTS(data));
 }
 
 void Model100Side::setOneLEDTo(uint8_t led, cRGB color) {
   uint8_t data[] = {TWI_CMD_LED_SET_ONE_TO,
                     led,
-                    color.b,
-                    color.g,
-                    color.r};
+                    pgm_read_byte(&gamma8[color.b]),
+                    pgm_read_byte(&gamma8[color.g]),
+                    pgm_read_byte(&gamma8[color.r])};
   uint8_t result = writeData(data, ELEMENTS(data));
 }