docs: add the link of xtensa isa doc to hlinterrupts.rst
@@ -88,3 +88,4 @@ Notes
- In theory, medium priority interrupts could also be handled in this way. ESP-IDF does not support this yet.
+ - To check Xtensa instruction set architecture (ISA), please refer to `Xtensa ISA Summary <https://www.cadence.com/content/dam/cadence-www/global/en_US/documents/tools/ip/tensilica-ip/isa-summary.pdf>`_.
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