Driver improvements (#535)

- New drivers:
  - SD SPI
  - spi_peripheral
  - touch_placeholder
  - display_placeholder
- Devicetree compiler:
  - Implement phandle-arrays
  - Implement device addresses
- Add placeholder drivers to all devices with a SPI display
- SPI driver: add `cs-pins` and set them to high on driver start
- FileSystem: add `file_system_set_owner()` and `file_system_get_owner()`
- File locking is now checking if the related `FileSystem` is part of a shared SPI bus
- Add `device_get_child_count()`
- SDMMC driver: Remove default of `slot` value
- Fix for Crowpanel Basic 3.5" display (add delay to booting)
- Fix for LilyGO T-HMI SD card mounting (delayed mounting by disabling it initially in the dts)

Platforms/platform-esp32/bindings/espressif,esp32-sdmmc.yaml

@@ -4,40 +4,40 @@ compatible: "espressif,esp32-sdmmc"
 
 properties:
   pin-clk:
-    type: phandle-array
+    type: phandles
     required: true
   pin-cmd:
-    type: phandle-array
+    type: phandles
     required: true
   pin-d0:
-    type: phandle-array
+    type: phandles
     required: true
   pin-d1:
-    type: phandle-array
+    type: phandles
     default: GPIO_PIN_SPEC_NONE
   pin-d2:
-    type: phandle-array
+    type: phandles
     default: GPIO_PIN_SPEC_NONE
   pin-d3:
-    type: phandle-array
+    type: phandles
     default: GPIO_PIN_SPEC_NONE
   pin-d4:
-    type: phandle-array
+    type: phandles
     default: GPIO_PIN_SPEC_NONE
   pin-d5:
-    type: phandle-array
+    type: phandles
     default: GPIO_PIN_SPEC_NONE
   pin-d6:
-    type: phandle-array
+    type: phandles
     default: GPIO_PIN_SPEC_NONE
   pin-d7:
-    type: phandle-array
+    type: phandles
     default: GPIO_PIN_SPEC_NONE
   pin-cd:
-    type: phandle-array
+    type: phandles
     default: GPIO_PIN_SPEC_NONE
   pin-wp:
-    type: phandle-array
+    type: phandles
     default: GPIO_PIN_SPEC_NONE
   bus-width:
     type: int
@@ -45,7 +45,6 @@ properties:
     description: Bus width in bits
   slot:
     type: int
-    default: 1
     enum: [0, 1]
     description: SDMMC host slot number (SDMMC_HOST_SLOT_0 or SDMMC_HOST_SLOT_1). On ESP32-P4, slot 0 uses the dedicated (non-GPIO-matrix) pins.
   max-freq-khz: