Added RGBA support for Android.

[pweglik]

I'm not sure about C++ and Kotlin practices, but I added function that performs RGBA -> ARGB frame buffer conversion. This way, you can use resize plugin with Skia Frame processor from vision camera v4.

[mrousavy]

Hey!

Thank you so much for your PR, that's pretty dope.

I wanna have a few changes in that code though.

1. Instead of passing the Image format to C++ with a custom created enum, we can just get the format of the JImage on the native side. Please use that approach instead, so in JImage we just add a int getFormat() method and compare it with the C++ Image Format types (HardwareBuffer maybe).
2. Instead of creating two functions in C++, we just stick to one single function (called imageToFrameBuffer) and add a switch in there. To me that sounds more logical
3. Any chance we can have iOS support in there?

[pweglik]

1. I added getFormat, but those int values come from: https://developer.android.com/reference/android/graphics/ImageFormat and https://developer.android.com/reference/android/graphics/PixelFormat#RGBA_8888
   I'm not really proficient in JNI and native code, so for now I left hardcoded in C++.
2. Done
3. I don't really know Swift/ObjC, so I can't help here. Also I think it works on iOS, as I've received no error when I set Camera props to 'rgb'.

[mrousavy]

Perfect!

[lin826]

Looking forward to the new release with this support for Android ❤️