Move C.RTLD_DEEPBIND do linux-specific file

[elezar]

This change ensures that the dl package works on Darwin platforms where C.RTLD_DEEPBIND is not defined.

Before this change:

➜  go-nvml git:(main) ✗ go build ./pkg/dl/...
# github.com/NVIDIA/go-nvml/pkg/dl
pkg/dl/dl.go:36:18: could not determine kind of name for C.RTLD_DEEPBIND
➜  go-nvml git:(main) ✗ echo $?
1

After this change:

➜  go-nvml git:(fix-deepbind) ✗ go build ./pkg/dl/...
➜  go-nvml git:(fix-deepbind) ✗ echo $?
0
```

[elezar]

/blossom-ci

[elezar]

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[elezar]

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[elezar]

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