Wrong Brand Name, NO GPU Info
When i run xmrig-amd - Brandname in API must be from GPU, not CPU.

```
/opt/xmrig-amd/xmrig-amd.log                                                                                                                                                                                                      1898/1898              100%
[2018-05-15 00:22:47]  * VERSIONS:     XMRig/2.6.1 libuv/1.9.1 OpenCL/2.0 gcc/6.3.0
[2018-05-15 00:22:47]  * CPU:                 Intel(R) Xeon(R) CPU E5-2660 0 @ 2.20GHz (1) x64 AES-NI
[2018-05-15 00:22:47]  * ALGO:         cryptonight, donate=1%
[2018-05-15 00:22:47]  * POOL #1:      mining.grftpool.com:3333
[2018-05-15 00:22:47]  * API PORT:     8081
[2018-05-15 00:22:47]  * COMMANDS:     'h' hashrate, 'p' pause, 'r' resume
[2018-05-15 00:22:47] compiling code and initializing GPUs. This will take a while...
[2018-05-15 00:22:47] #0, GPU #0 (Radeon RX 570 Series), intensity: 768 (8/256), cu: 32
[2018-05-15 00:23:03] new job from mining.grftpool.com:3333 diff 2000
[2018-05-15 00:23:03] use pool mining.grftpool.com:3333 18.197.112.104
[2018-05-15 00:23:05] accepted (1/0) diff 2000 (81 ms)
[2018-05-15 00:23:06] accepted (2/0) diff 2000 (83 ms)
[2018-05-15 00:23:11] accepted (3/0) diff 2000 (83 ms)
[2018-05-15 00:23:12] accepted (4/0) diff 2000 (82 ms)
```

In browser API absent info about GPU.
```
{
    "id": "9e9064d08c64b460",
    "worker_id": "z820",
    "version": "2.6.1",
    "kind": "amd",
    "ua": "XMRig/2.6.1 (Linux x86_64) libuv/1.9.1 gcc/6.3.0",
    "cpu": {
        "brand": "       Intel(R) Xeon(R) CPU E5-2660 0 @ 2.20GHz",
        "aes": true,
        "x64": true,
        "sockets": 1
    },
    "algo": "cryptonight",
    "hugepages": false,
    "donate_level": 1,
    "hashrate": {
        "total": [
            550.4,
            550.86,
            0.0
        ],
        "highest": 551.46,
        "threads": [
            [
                550.4,
                550.86,
                0.0
            ]
        ]
    },
    "results": {
        "diff_current": 128001,
        "shares_good": 14,
        "shares_total": 14,
        "avg_time": 14,
        "hashes_total": 184000,
        "best": [
            365428,
            303373,
            95859,
            83354,
            80069,
            12078,
            11640,
            9200,
            8507,
            7451
        ],
        "error_log": []
    },
    "connection": {
        "pool": "mining.grftpool.com:3333",
        "uptime": 198,
        "ping": 81,
        "failures": 0,
        "error_log": []
    }
}
```

Also why   **"hugepages": false,** ?
I'm run this before:
```
root@z820:/opt/xmrig# echo 128 > /proc/sys/vm/nr_hugepages
root@z820:/opt/xmrig# sysctl -w vm.nr_hugepages=128

```