Fix for mount point detection on Android with latest toolchain.

[kollivier]

Summary

On the Android devices I'm testing on, mount works and returns output in the format defined for the Linux parser. This modifies the detection logic to try that first, then fall back to the RAW_MOUNT_PARSER syntax if it fails.

Reviewer guidance

To test, you need an Android device with external storage, like an SD Card or possibly a USB device. You also need to go into the app settings and enable storage permissions manually until the app support branch has the ability to prompt for permissions.

References

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[indirectlylit]

visual inspection looks reasonable but i have not tested. Merging in so it doesn't get stale