Improve backlight PWM pin support (#6202)

* Improve backlight PWM pin support

* I accidentally an equals sign

* Another typo

* Order by pin number

* Throw an error if backlight pin is C4 or C5 on 16/32U4

* Use else for clarity

* Minor alignment adjustments

1 files changed, 1 insertions, 3 deletions

diff --git a/docs/hardware_avr.md b/docs/hardware_avr.md
index 7c28ab6db..c6987d1bd 100644
--- a/docs/hardware_avr.md
+++ b/docs/hardware_avr.md
@@ -125,7 +125,7 @@ To configure a keyboard where each switch is connected to a separate pin and gro
 
 ### Backlight Configuration
 
-By default QMK supports backlighting on pins `B5`, `B6`, and `B7`. If you are using one of those you can simply enable it here. For more details see the [Backlight Documentation](feature_backlight.md).
+QMK supports backlighting on most GPIO pins. A select few of these can be driven by the MCU in hardware. For more details see the [Backlight Documentation](feature_backlight.md).
 
 ```c
 #define BACKLIGHT_PIN B7
@@ -134,8 +134,6 @@ By default QMK supports backlighting on pins `B5`, `B6`, and `B7`. If you are us
 #define BREATHING_PERIOD 6
 ```
 
-?> You can use backlighting on any pin you like, but you will have to do more work to support that. See the [Backlight Documentation](feature_backlight.md) for more details.
-
 ### Other Configuration Options
 
 There are a lot of features that can be configured or tuned in `config.h`. You should see the [Config Options](config_options.md) page for more details.