soc: silabs: siwx91x: enable BLE stack bypass for host-driven operation

[Arunnagelly]

Set SL_SI91X_BT_BLE_STACK_BYPASS_ENABLE in ble_ext_feature_bit_map to support host-driven BT/BLE stack operation on SiWx91x devices.

When enabled:

• Events are delivered directly to the host, bypassing internal stack processing
• Ensures critical events like CARD_READY reach the host reliably
• Allows external host stack to control BT/BLE operations
• Provides more memory to the application, as the internal stack is bypassed

This change enables direct event packet delivery from the firmware event handler, ensuring proper operation when the internal BT stack is bypassed.

Required for BT/BLE tester and host-controlled stack configurations.

[github-actions]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud