Update list of debugging switches

[adrastogi]

There are a couple more debugging switches that we should ensure we document. Filing this to track for the time being.

--webnn-ort-ep-device - https://chromium-review.googlesource.com/c/chromium/src/+/7111738

--webnn-ort-ignore-ep-blocklist - https://chromium-review.googlesource.com/c/chromium/src/+/7133323

[ibelem]

Thanks @adrastogi for the feedback, they've been added in https://github.com/webmachinelearning/webnn-docs/pull/48/files#diff-2b3c362fc81ecfcfb33612945e63f8be1ba5eec50ea650bf936d90f7e785b6f3R139 , PTAL

• https://webnn.io/en/api-reference/browser-compatibility/chrome-flags#--webnn-ort-ep-device
• https://webnn.io/en/api-reference/browser-compatibility/chrome-flags#--webnn-ort-ignore-ep-blocklist
• https://webnn.io/en/learn/get-started/debug#additional-debug-options

[adrastogi]

Looks great, thanks @ibelem for making these updates!