mb/google/fatcat: Remove NPK device from fatcat and francka variants

This commit removes the `device ref npk on end` from the
`overridetree.cb` files for the `fatcat` and `francka` variants
of the `google/fatcat` mainboard. This effectively disables
the NPK device for these configurations (because `npk` is default
set to disable).

BUG=b:328770565
TEST=Able to build google/fatcat.

Change-Id: I9dda20552781af6b29a2156cbc1e3bea352c5836
Signed-off-by: Subrata Banik <subratabanik@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/87453
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Jamie Ryu <jamie.m.ryu@intel.com>
Reviewed-by: Kapil Porwal <kapilporwal@google.com>

src/mainboard/google/fatcat/variants/fatcat/overridetree.cb

@@ -921,7 +921,6 @@ chip soc/intel/pantherlake
 		end
 
 		device ref smbus on end
-		device ref npk on end
 		device ref hda on
 			chip drivers/intel/soundwire
 				device generic 0 on

src/mainboard/google/fatcat/variants/francka/overridetree.cb

@@ -273,7 +273,6 @@ chip soc/intel/pantherlake
 		end # M.2 SSD
 
 		device ref smbus on end
-		device ref npk on end
 		device ref hda on
 			chip drivers/sof
 				register "spkr_tplg" = "max98360a"