chore: dev arm64 SDL2 and other arm64 specific dependencies for firmware building

[pfeerick]

Changes:

• chore: update actions to later versions
• chore: remove funding.yml so org copy is used
• feat: build SDL2 from source for both x64 and arm64

Warning

Remember to bump QT version in MacOS runner action from 6.9.0 to 6.9.3 for consistency.

This gets us one step closer to arm64 native building, particularly for the build container on Apple Silicon, but since there is no install source for an arm64/aarch64 qt6 (Qt doesn't provide official prebuilt binaries for Linux ARM64 desktop), can only go so far for now. We would probably have to build from source(prebuild and cache, ideally) if we wanted to pursue this further.

root@a95b3c6e843d:/workspaces/edgetx# uvx --from aqtinstall aqt list-qt linux desktop --arch 6.9.3
linux_gcc_64
root@a95b3c6e843d:/workspaces/edgetx# uvx --from aqtinstall aqt list-qt linux desktop --arch 6.10.1
linux_gcc_64

Issues still outstanding (qt6 not present notwithstanding):

-- Could NOT find WrapVulkanHeaders (missing: Vulkan_INCLUDE_DIR) 
-- Could NOT find Cups (missing: CUPS_LIBRARIES CUPS_INCLUDE_DIR) 
-- Could NOT find OpenSSL, try to set the path to OpenSSL root folder in the system variable OPENSSL_ROOT_DIR (missing: OPENSSL_INCLUDE_DIR)
-- linuxdeploy x86/x64 issues - linuxdeploy-plugin-qt-x86_64.AppImage: 1: cannot create ��@xb@8: Operation not permitted

CUPS/VulkanHeaders might have been resolved by last commit. There is an aarch64 version of linuxdeploy available also, and cmake can be taught to switch automatically as needed (via EdgeTX/edgetx#6882). Meaning the actual only outstanding issues I can see so at present is something is still calling a x88_64 process per below, and QT6 not present 🤭

i.e.

root@94b64c2212f7:/workspaces/edgetx/build-tx16s# cmake --build . --target native-configure --parallel 4
loading initial cache file /workspaces/edgetx/build-tx16s/native-prefix/tmp/native-cache-Release.cmake
rosetta error: failed to open elf at /lib64/ld-linux-x86-64.so.2

[pfeerick]

Ok, that run was better... 36 odd minutes instead of 50... lets see if this helps this / future builds.

[pfeerick]

Caching seems to be working, and was able to test this on Macbook Air M4 for building firmware. Companion building seems to be an issue as it seems OpenGL and "WrapOpenGL" weren't found, thus no Qt6Gui nor Qt6Widgets.

[pfeerick]

This also works on Mac Mini M4 running Apple Containers...

i.e. building TX12MK2 firmware

container run -it --memory 12G --cpus 6 --rm -v $(pwd):/src ghcr.io/edgetx/edgetx-dev:pr-41 bash

---
FLAVOR=tx12mk2 tools/build-gh.sh
---

Totals         KB    usage  of ttl      KB free
  Flash:   502.71   98.18%     512         9.29
  CCRAM:    45.01   70.32%      64        18.99
  SRAM1:     7.82    6.98%     112       104.18
  SRAM2:     0.00    0.00%      16        16.00

[100%] Built target firmware-size
+ rm -f CMakeCache.txt arm-none-eabi/CMakeCache.txt
+ '[' -f arm-none-eabi/firmware.uf2 ']'
+ mv arm-none-eabi/firmware.bin ../tx12mk2-0197d63ea.bin
root@14a856e6-c102-4ea4-9774-a06b3630078e:/src#