[orchagent] PORT_PHY_ATTR logs ERR on VS for unsupported attributes (RX_SIGNAL_DETECT)

[rustiqly]

Description

After merging #3957 (PORT_PHY_ATTR flex counter support) and #4017 (PORT_SERDES_ATTR), orchagent logs ERR-level messages on VS (Virtual Switch) platforms for unsupported PHY attributes:

ERR swss#orchagent: :- verifyPortSupportsAllPhyAttr: PORT_PHY_ATTR: Port Ethernet0 does not support RX_SIGNAL_DETECT attribute (status=-15)
ERR swss#orchagent: :- verifyPortSupportsAllPhyAttr: PORT_PHY_ATTR: Port Ethernet1 does not support RX_SIGNAL_DETECT attribute (status=-15)

This causes VS/KVM CI test failures due to unexpected ERR-level syslog messages being matched by log analyzers.

Root Cause

verifyPortSupportsAllPhyAttr() logs at ERR level when SAI returns SAI_STATUS_NOT_SUPPORTED (-15). On VS, the virtual SAI doesn't implement PHY attributes like SAI_PORT_ATTR_RX_SIGNAL_DETECT, SAI_PORT_ATTR_FEC_ALIGNMENT_LOCK, and SAI_PORT_ATTR_RX_SNR, so every port triggers this error.

Impact

• Causes spurious test failures in VS/KVM CI pipelines (e.g., seen in sonic-buildimage PR #25552 CI)
• ERR-level logs for expected platform limitations add noise to syslog

Suggested Fix

Downgrade the log level from ERR to WARNING or INFO when SAI returns SAI_STATUS_NOT_SUPPORTED. This is an expected condition on platforms that don't support PHY attribute polling — it's not an error.

Alternatively, skip PHY attribute flex counter registration on platforms that don't support these attributes.

References

• Add PORT_PHY_ATTR flex counter support #3957 — Add PORT_PHY_ATTR flex counter support (merged 2026-02-11)
• [202505] Add PORT_SERDES_ATTR flex counter support in orchagent #4017 — Add PORT_SERDES_ATTR flex counter support (merged 2026-02-12)
• sonic-buildimage#25406 — swss submodule bump that pulled in these changes