Parallels provider: Fixed mount options for synced folders

Mount options "dmode" and "fmode" are unavailable for "prl_fs"
filesystem. Use mount option "share", which provides liberal access
permissions to shared folders.

Related issue:
https://github.com/Parallels/vagrant-parallels/issues/135
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Merge pull request #1090 from legal90/master

Parallels provider: Fixed mount options for synced folders
Merge pull request #2 from puphpet/master

Update from origin