Improve driver uninstall workflow

[petrutlucian94]

This change fixes a few issues of the driver install and uninstall code:

• remove WNBD disks associated to every adapter, not just the first one
• double check the device class GUID before opening
• merges the FindWnbdAdapterDevice and WnbdOpenAdapterEx functions.
• improved logging
  • add info messages for the executed actions
  • avoid messeages such as "funcName failed with ", using more user friendly messages which describe the failed action
  • include the INF path in the error msg when failing to process it
  • when an uninstall is requested, avoid logging errors if there's no WNBD adapter and proceed to removing the driver
  • add warnings when dealing with leaked devnodes
• ensure that errors get propagated
• avoid unnecessary "goto" statements
• use fs::path::filename for retrieving filenames
• add some null pointer checks to avoid some compiler warnings
• other minor cleanups

Signed-off-by: Lucian Petrut lpetrut@cloudbasesolutions.com