gen_idt: add -d switch for extra debug info

Previously, gen_idt's code had to be modified to get this information.
We now print it by default when building with V=1

Change-Id: I31bd6c5b851d6280ebcedaab97bd02b8331a2f24
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>