util/ifdtool: Add support for Denverton SoC

Denverton is a special version of IFD2 flash layout.  It defines
10GbE firmware regions (11/12) and the IE (10) region which
other IFD2 platforms do not have.  Denverton does not include the
legacy GbE region (3) or the EC region (8) which other IFD2
platforms do have.

TEST='ifdtool -p dnv coreboot.rom' and verify correct output

Signed-off-by: Jeff Daly <jeffd@silicom-usa.com>
Change-Id: I15939ce4672123f39a807d63c13ba7df98c57523
Reviewed-on: https://review.coreboot.org/c/coreboot/+/60830
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/soc/intel/denverton_ns/Kconfig

@@ -174,4 +174,8 @@ config USE_DENVERTON_NS_FSP_CAR
 
 endchoice
 
+config IFD_CHIPSET
+	string
+	default "dnv"
+
 endif ## SOC_INTEL_DENVERTON_NS