[SYCL][ABI] Guard member equal comparison operator function members and provide free friend functions instead (#22484)
This PR guards the member functions for equal comparison `==` & `!=` for
the `event`, `queue`, `device`, `context` classes in
`__INTEL_PREVIEW_BREAKING_CHANGES` and provides free friend functions
instead
fixes #22474
fixes #22473
fixes #22472
fixes #22471