Add directory of wmic.exe to path as required by csi-proxy

[laozc]

Reason for PR:
Fixes wmic.exe not found during CSI driver registration.

I0131 16:03:31.383613    6684 main.go:121] Received NotifyRegistrationStatus call: &RegistrationStatus{PluginRegistered:false,Error:RegisterPlugin error -- plugin registration failed with err: rpc error: code = Internal desc = failed to get system uuid for node VM with error: rpc error: code = Unknown desc = exec: "wmic": executable file not found in %PATH%,}
E0131 16:03:31.383613    6684 main.go:123] Registration process failed with error: RegisterPlugin error -- plugin registration failed with err: rpc error: code = Internal desc = failed to get system uuid for node VM with error: rpc error: code = Unknown desc = exec: "wmic": executable file not found in %PATH%, restarting registration container.

https://github.com/kubernetes-csi/csi-proxy/blob/07be14dabebca5d1590e670f9a796fcfce44d6e6/pkg/os/system/api.go#L37

Issue Fixed:
Issue #358

Requirements

• Sqaush commits
• Documentation
• Tests

Notes:

[aravindhp]

/lgtm

[aravindhp]

/assign @jsturtevant @marosset

for approval

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