tests: kernel: sleep: Fix uninitialised variable warning

[stephanosio]

This commit sets an initial value of 0 for the elapsed_ms variable,
which may be used uninitialised when the while loop below does not
execute.

This fixes the "‘elapsed_ms’ may be used uninitialized" warning
generated by the GCC 12.

Signed-off-by: Stephanos Ioannidis root@stephanos.io

[chen-png]

added a backport label for v3.1-branch, as this also will report same build warning on v3.1-branch with zephyr sdk 0.15.0.

[stephanosio]

Zephyr SDK 0.15.0 is not supposed to work with any Zephyr versions below the upcoming 3.2.0 release and the main branch.

[chen-png]

we enabled hardware daily testing for v3.1-branch with Zephyr SDK 0.15.0, it worked well except for those same build warnings as the main branch before, so I want to cherry-pick those fixes.
So you mean that for v3.1-branch, we should still use the old SDK revision 0.14 rather then the latest 0.15.0, right?

[stephanosio]

So you mean that for v3.1-branch, we should still use the old SDK revision 0.14 rather then the latest 0.15.0, right?

Yes.

[chen-png]

thanks for your explanation, I will still use sdk 0.14 for v3.1-branch testing and close those backport patches.