NTFS: Fix some corruption reading compressed NTFS files, reported by bsobel [#5206]
NTFS: Fix some corruption reading compressed NTFS files, reported by bsobel [#5206]

Fixes two assumptions:
* The start of a read is aligned with the start of a compression block
* The start of a compression block is aligned with the start of a data run.

Neither of which is true in non-trivial cases.

quamotion/discutils,drebrez/DiscUtils,breezechen/DiscUtils,breezechen/DiscUtils