ACPICA: debugger: surround field unit output with braces '{'

ACPICA commit 76ca57291d007d33087982a4b28cd1ee9bcd37a6

This helps differentiate the type of named objects between field
units and buffers. In other words, without this symbol, it would be
difficult to tell whether a particular named object is a buffer or a
field unit.

Link: https://github.com/acpica/acpica/commit/76ca5729


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