Add sample platformio_override.ini for GPU Fan Controller

usermods/GPU_Fan_Controller/platformio_override.sample.ini

@@ -0,0 +1,27 @@
+; PlatformIO override file for GPU Fan Controller Usermod
+; 
+; Copy this file to the WLED root directory and rename to platformio_override.ini
+; Then build with: pio run -e esp32dev_gpu_fan -t upload
+
+[env:esp32dev_gpu_fan]
+extends = env:esp32dev
+board = esp32dev
+platform = ${esp32.platform}
+platform_packages = ${esp32.platform_packages}
+build_unflags = ${common.build_unflags}
+build_flags = ${common.build_flags} ${esp32.build_flags}
+  -D USERMOD_GPU_FAN_CONTROLLER
+  -D PWM_FAN_PIN=13
+; Add these lib_deps if they're not already included
+lib_deps = ${esp32.lib_deps}
+custom_usermods = GPU_Fan_Controller
+
+; Alternative: ESP32-S3 build
+[env:esp32s3dev_gpu_fan]
+extends = env:esp32s3dev_8MB
+board = esp32-s3-devkitc-1
+build_flags = ${common.build_flags} ${esp32s3.build_flags}
+  -D USERMOD_GPU_FAN_CONTROLLER
+  -D PWM_FAN_PIN=13
+lib_deps = ${esp32s3.lib_deps}
+custom_usermods = GPU_Fan_Controller