Improvements & fixes for HUB75

- added proper config parameters to allow multiple panels
- added config checks
- fixed crashes on S3
- changed constant variables to constexpr
- added "wled.h" to bus_manager.cpp and removed local function prototypes (needed for buffer allocations)
- speed optimisations: yields about 10% higher FPS
- proper brightness handling
- updated platformio_override.sample.ini
- some code cleanup

Author: DedeHai

platformio_override.sample.ini

@@ -529,6 +529,7 @@ lib_deps = ${env:esp32dev.lib_deps}
 # ------------------------------------------------------------------------------
 # Hub75 examples
 # ------------------------------------------------------------------------------
+# Note: some panels may experience ghosting with default full brightness. use -D WLED_HUB75_MAX_BRIGHTNESS=239 or lower to fix it.
 
 [env:esp32dev_hub75]
 board = esp32dev
@@ -561,15 +562,18 @@ build_flags = ${common.build_flags}
 
 [env:adafruit_matrixportal_esp32s3]
 ; ESP32-S3 processor, 8 MB flash, 2 MB of PSRAM, dedicated driver pins for HUB75
+; If board file is missing, copy it manually into the boards folder: .platformio\platforms\espressif32@src-xxxsomehashnumberxxx\boards
+; https://github.com/platformio/platform-espressif32/blob/master/boards/adafruit_matrixportal_esp32s3.json
 board = adafruit_matrixportal_esp32s3
 platform = ${esp32s3.platform}
 platform_packages =
 upload_speed = 921600
 build_unflags = ${common.build_unflags}
 build_flags = ${common.build_flags} ${esp32s3.build_flags} -D WLED_RELEASE_NAME=\"ESP32-S3_4M_qspi\"
-  -DARDUINO_USB_CDC_ON_BOOT=1 -DARDUINO_USB_MODE=1      ;; for boards with USB-OTG connector only (USBCDC or "TinyUSB")
+  -DARDUINO_USB_CDC_ON_BOOT=1 ;; for boards with USB-OTG connector only (USBCDC or "TinyUSB")
+  -DARDUINO_USB_MODE=1      ; if board does not boot after reset/powerup, try setting this to 0 (or open serial monitor)
   -DBOARD_HAS_PSRAM
-  -DLOLIN_WIFI_FIX ; seems to work much better with this
+  -DLOLIN_WIFI_FIX ; seems to work much better with this (sets lower TX power)
   -D WLED_WATCHDOG_TIMEOUT=0
   -D WLED_ENABLE_HUB75MATRIX -D NO_GFX
   -D S3_LCD_DIV_NUM=20 ;; Attempt to fix wifi performance issue when panel active with S3 chips
@@ -595,7 +599,7 @@ build_unflags = ${common.build_unflags}
 build_flags = ${common.build_flags} ${esp32s3.build_flags} -D WLED_RELEASE_NAME=\"esp32S3_16MB_PSRAM_HUB75\"
               -DARDUINO_USB_CDC_ON_BOOT=1 -DARDUINO_USB_MODE=1      ;; for boards with USB-OTG connector only (USBCDC or "TinyUSB")
               -DBOARD_HAS_PSRAM
-              -DLOLIN_WIFI_FIX ; seems to work much better with this
+              -DLOLIN_WIFI_FIX ; seems to work much better with this (sets lower TX power)
               -D WLED_WATCHDOG_TIMEOUT=0
               -D WLED_ENABLE_HUB75MATRIX -D NO_GFX 
               -D S3_LCD_DIV_NUM=20 ;; Attempt to fix wifi performance issue when panel active with S3 chips