ACPICA: Debugger: remove redundant assignment on obj_desc

ACPICA commit f530f1acb3128136ad97c715fdaebbbeff283ee2

Pointer obj_desc is being initialized with a value that is never
read and it is being updated later with a new value. The initialization
is redundant and can be removed.

Addresses-Coverity: ("Unused value")

Link: https://github.com/acpica/acpica/commit/f530f1ac


Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Erik Schmauss <erik.schmauss@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>