RFR: JDK-8231721: jpackage --install-dir should reject system dirs on Linux

[Alexander Matveev]

Looks good.

On 10/1/19 3:00 PM, Alexey Semenyuk wrote:
> Please review the jpackage fix for bug [1] at [2].
>
> This is a fix for the JDK-8200758-branch branch of the open sandbox 
> repository (jpackage).
>
> [1] https://bugs.openjdk.java.net/browse/JDK-8231721
>
> [2] http://cr.openjdk.java.net/~asemenyuk/8231721/webrev.00/
>