|SUCCESS| pw161863 [RFC] net/cnxk: only build if platform is specified

[qemudev at loongson.cn]

Test-Label: loongarch-compilation
Test-Status: SUCCESS
https://dpdk.org/patch/161863

_Compilation OK_

Submitter: Stephen Hemminger <stephen at networkplumber.org>
Date: Tue, 24 Feb 2026 12:37:09 -0800
DPDK git baseline: Repo:dpdk-next-net-mrvl
  Branch: for-next-net
  CommitID: af06ac4c9ad74517f9f3ebf45d3e957845337ea3

161863 --> meson & ninja build successfully

Test environment and result as below:

+---------------------+----------------+
|     Environment     | compilation    |
+---------------------+----------------+
| Loongnix-Server 8.3 | PASS           |
+---------------------+----------------+

Loongnix-Server 8.3
    Kernel: 4.19.190+
    Compiler: gcc 8.3