Change minimum Tizen version 5.5 to 6.0

[JSUYA]

• Remove Tizen 5.5 support.
• Remove Wearable support.

[JSUYA]

Hi @swift-kim I have a question.
This PR's build test is failing. I tried cleaning local git and building with gclient sync, but i can't reproduce the build failure. Even in my repo where this patch was pushed builds well.
(https://github.com/JSUYA/embedder/actions/runs/8889817049/job/24408777062)

At download.tizen.org, there is a version difference between 5.5 and 6.5 libstdc++, but between 6.0 and 6.5 is not different.
As far as I know, the --system-cxx command should work normally in 6.0 as well.
I haven't found the reason for this. Do you know a solution to this problem?

[swift-kim]

Everything looks fine but I think you need to clear the GitHub Actions cache (or do not delete Generate Tizen 6.0 sysroot and --target-sysroot).

The gclient sync hook should have generated a Tizen 5.5 sysroot in the default location (src/sysroot) and the files are being cached wrongly.

[JSUYA]

Everything looks fine but I think you need to clear the GitHub Actions cache (or do not delete Generate Tizen 6.0 sysroot and --target-sysroot).

Thanks. I will add Generate Tizen 6.0 sysroot.
Actually, I don't know if the cache for the default version worked well. (Part cached with sysroot-5.5)

The gclient sync hook should have generated a Tizen 5.5 sysroot in the default location (src/sysroot) and the files are being cached wrongly.

Because I changed the default version of generate_sysroot.py to 6.0, Tizen 6.0 sysroot is generated in src/sysroot, so I think the sysroot generated with gclient sync + hook is Tizen 6.0 sysroot.
Adding the Generate Tizen 6.0 sysroot job will solve the problem, but I don't know why src/sysroot is not working properly.

[swift-kim]

Because the sysroot is not generated again (overwritten) if already present (i.e. cached).

Could you please refrain from force-pushing changes? It makes it difficult to track changes and thus is not good for reviewability.

[JSUYA]

rebased pr

[JSUYA]

@swift-kim Could you please approve?, if there is no more code that needs to be fixed. It seems to applied most of the reviews.