ci android

[mrobertseidowsky-gpsw]

Description:

This PR allows to:

• Compile ffmpeg sources for different Android host,
• Compile sxplayer sources for different Android host,
• Build libnodegl lib for each target,
• Libnodegl tests are compiled but not runned (skipped).

One cross compilation file (.ini) per architecture (i.e processor type on the phone) is given as meson input.

Architectures are:

• x86_64: x86 processor 64-bit,
• arm: arm processor 32-bit,
• aarch64: arm processor 64-bit.

A compiler for each architecture is directly provided from the Android ndk toolchain on the remote machine.

Notes:

• meson is installed with pip to receive the most up-to-date version (apt provides version 0.53.2 which is not compatible with project requirement (>=0.57.0) while pip provides version 0.62.0).
• About the dependencies, sxplayer + ffmpeg are being rebuilt at the moment, but a solution that catch artifacts dropped on sxplayer repository may be considered in the future.
• The files tree has been reshaped because:
  • by default meson set /usr/local as prefix in the .pc file which can not be written on github action remote machine (only write access to home).
  • by default the generated files has this structure (tree pruned with only relevant files):

builddir
├── libsxplayer.so
├── meson-private
│   ├── libsxplayer.pc
├── sxplayer.h

• So a more standard tree is created in the home thanks to the command meson install.
  • prefix /usr/local becomes /home/runner/usr/local
  • structure of files becomes:

/home/runner
├── usr
    ├── local
        ├── lib
            ├── libsxplayer.so
	    ├── pkgconfig
 	        ├── libsxplayer.pc
        ├── include
            ├── sxplayer.h

• This structure is, at the end easily understood by meson when building libnodegl.