[AMD] [AGENTX] dsv4-fp4-mi355x-sglang-agentic-mtp: add TP8 dp-off conc 1,2 arm

Add a pure-TP (dp-attn false) low-concurrency arm (conc 1,2, spec-decoding mtp)
alongside the existing DEP conc 4-32 arm.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: seungrokj

configs/amd-master.yaml

@@ -1695,6 +1695,7 @@ dsv4-fp4-mi355x-sglang-agentic-mtp:
     agentic-coding:
     - dram-utilization: 0.80
       search-space:
+      - { tp: 8, dp-attn: false, kv-offloading: none, conc-list: [1, 2], spec-decoding: mtp }
       - { tp: 8, dp-attn: true, kv-offloading: none, conc-list: [4, 8, 16, 32], spec-decoding: mtp }
 
 # MiniMax-M3 MXFP8 MI355X recipe: