🔨 Creality v4 with STM32 HAL (#21999)

- New STM32 env for Creality V4 boards.
- Separate Libmaple targets into their own `ini` file.
- Temporarily remove unusable targets from `pins.h`.

Co-authored-by: ellensp <ellensp@hotmsil.com>
Co-authored-by: Scott Lahteine <github@thinkyhead.com>

buildroot/tests/STM32F103RC_btt_USB_maple

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+#
+# Build tests for STM32F103RC BigTreeTech (SKR Mini v1.1) with LibMaple STM32F1 HAL
+#
+
+# exit on first failure
+set -e
+
+#
+# Build with the default configurations
+#
+restore_configs
+opt_set MOTHERBOARD BOARD_BTT_SKR_MINI_V1_1 SERIAL_PORT 1 SERIAL_PORT_2 -1 BAUDRATE_2 115200
+exec_test $1 $2 "BigTreeTech SKR Mini v1.1 - Basic Configuration" "$3"
+
+# clean up
+restore_configs