This commit centralizes equality-check behavior and removes duplicated
macro implementations across protocol stacks.
Major changes:
- add `common/utils/eq_check.h` with shared `_EQ_CHECK_*`,
`EQ_CHECK_GENERIC`, and optional-IE pointer helpers
- replace E1AP/F1AP/NAS local equality macros and call sites with
the shared helpers
- remove duplicated layer-specific error/equality macro definitions from
common headers and switch includes to `eq_check.h`
- update CMake test flags to define `ENABLE_TESTS` for `e1ap_lib`,
and 5GS NAS libraries; drop `E1AP_LOG_ERRORS` - equality-check/error
printing is now consistently controlled by `ENABLE_TESTS`