Skip `_tpause` call for `_M_ARM64EC` in spin_pause.cc. (#24942)
### Description
<!-- Describe your changes. -->
Skip `_tpause` call for `_M_ARM64EC` in spin_pause.cc.
### Motivation and Context
<!-- - Why is this change required? What problem does it solve?
- If it fixes an open issue, please link to the issue here. -->
Fix link error on ARM64EC for `_tpause` unresolved external symbol.