Adkernel: documenting ergadx alias

Documenting prebid/Prebid.js#7544

dev-docs/bidders/ergadx.md

@@ -0,0 +1,27 @@
+---
+layout: bidder
+title: eRGADX
+description: eRGADX Bidder Adaptor
+pbjs: true
+pbs: true
+biddercode: ergadx
+aliasCode : adkernel
+media_types: banner, native, video
+gdpr_supported: true
+usp_supported: true
+coppa_supported: true
+pbs_app_supported: true
+schain_supported: true
+---
+
+### Note:
+
+The eRGADX bidding adapter requires setup and approval before implementation. Please reach out to <prashant.musale@erelego.com> for more details.
+
+### Bid Params
+
+{: .table .table-bordered .table-striped }
+| Name | Scope | Description | Example | Type |
+|----------|----------|-----------------------|---------------------------|----------|
+| `host` | required | RTB host | `'cpm.ergadx.com'` | `string` |
+| `zoneId` | required | Zone Id | 30164 | `integer` |