ACPI: dock: cleanup the uid patch

Make uid sysfs file error path free memory, and cleanup sysfs file
when removing driver.  Also fix CodingStyle violations.

Signed-off-by:  Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Cc: Illya A. Volynets-Evenbakh <ilya@total-knowledge.com>
Signed-off-by: Len Brown <len.brown@intel.com>