refactor: Remove unimportant labels

Removed "label" properties which no longer have any function.

Labels are still used as layer names and as identifiers for sending
behaviors between sides of a split keyboard, so those have been left
alone for now.

app/boards/shields/two_percent_milk/boards/nice_nano.overlay

@@ -25,7 +25,6 @@
 
     led_strip: ws2812@0 {
         compatible = "worldsemi,ws2812-spi";
-        label = "WS2812";
 
         /* SPI */
         reg = <0>; /* ignored, but necessary for SPI bindings */

app/boards/shields/two_percent_milk/boards/nice_nano_v2.overlay

@@ -25,7 +25,6 @@
 
     led_strip: ws2812@0 {
         compatible = "worldsemi,ws2812-spi";
-        label = "WS2812";
 
         /* SPI */
         reg = <0>; /* ignored, but necessary for SPI bindings */

app/boards/shields/two_percent_milk/boards/nrfmicro_11.overlay

@@ -25,7 +25,6 @@
 
     led_strip: ws2812@0 {
         compatible = "worldsemi,ws2812-spi";
-        label = "WS2812";
 
         /* SPI */
         reg = <0>; /* ignored, but necessary for SPI bindings */

app/boards/shields/two_percent_milk/boards/nrfmicro_11_flipped.overlay

@@ -25,7 +25,6 @@
 
     led_strip: ws2812@0 {
         compatible = "worldsemi,ws2812-spi";
-        label = "WS2812";
 
         /* SPI */
         reg = <0>; /* ignored, but necessary for SPI bindings */

app/boards/shields/two_percent_milk/boards/nrfmicro_13.overlay

@@ -25,7 +25,6 @@
 
     led_strip: ws2812@0 {
         compatible = "worldsemi,ws2812-spi";
-        label = "WS2812";
 
         /* SPI */
         reg = <0>; /* ignored, but necessary for SPI bindings */

app/boards/shields/two_percent_milk/two_percent_milk.overlay

@@ -12,8 +12,6 @@
     kscan0: kscan {
         compatible = "zmk,kscan-gpio-direct";
 
-        label = "KSCAN";
-
         input-gpios
             = <&pro_micro 4 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
             , <&pro_micro 5 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>