dynamic host volumes: apply requested perms

[lgfa29]

Description

The mkdir dynamic host volume plugin uses the os.MkdirAll() function to create the host volume directory, but the permissions passed are affected by the user's umask, which can result in unexpected directory permissions.

For example, with the common default umask of 022, creating a dynamic host volume with mode = "0777" results in a directory with permissions set to 0755.

Testing & Reproduction steps

1. Check user umask is not 000.
2. Create a dynamic host volume using the mkdir plugin with mode = "0777".
3. Verify the host volume directory permission is 0777.

Links

The permission bits perm (before umask) are used for all directories that MkdirAll creates.

https://pkg.go.dev/os#MkdirAll

Closes #26190

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Changes to Security Controls

Are there any changes to security controls (access controls, encryption, logging) in this pull request? If so, explain.

[pkazmierczak]

LGTM! Thanks for the contribution, Luiz!

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