Merge develop into main (#303)

- `DisplayDevice` improvements related `DisplayDriver`
- Replaced incorrect usage of `spiBusHandle` with `spiHostDevice` in all SPI display devices
- Disabled `DisplayDriver` support for RGB displays for now
- Updated `GraphicsDemo` project for the above changes
- TactilityC improvements:
  - created `tt_hal_device_find()`
  - created `tt_hal_display_*`
  - created `tt_hal_touch_*`
  - created `tt_lvgl_*`
  - export `tt_app_*` calls

TactilityC/Source/tt_kernel.cpp

@@ -0,0 +1,42 @@
+#include "tt_kernel.h"
+#include <Tactility/kernel/Kernel.h>
+
+extern "C" {
+
+void tt_kernel_delay_millis(uint32_t milliseconds) {
+    tt::kernel::delayMillis(milliseconds);
+}
+
+void tt_kernel_delay_micros(uint32_t microSeconds) {
+    tt::kernel::delayMicros(microSeconds);
+}
+
+void tt_kernel_delay_ticks(TickType ticks) {
+    tt::kernel::delayTicks((TickType_t)ticks);
+}
+
+TickType tt_kernel_get_ticks() {
+    return tt::kernel::getTicks();
+}
+
+TickType tt_kernel_millis_to_ticks(uint32_t milliSeconds) {
+    return tt::kernel::millisToTicks(milliSeconds);
+}
+
+bool tt_kernel_delay_until_tick(TickType tick) {
+    return tt::kernel::delayUntilTick(tick);
+}
+
+uint32_t tt_kernel_get_tick_frequency() {
+    return tt::kernel::getTickFrequency();
+}
+
+uint32_t tt_kernel_get_millis() {
+    return tt::kernel::getMillis();
+}
+
+unsigned long tt_kernel_get_micros() {
+    return tt::kernel::getMicros();
+}
+
+}