util/sconfig: Add LPC and ESPI buses

Picasso has an LPC and eSPI bridge on the same PCI DEVFN. They can both
be active at the same time. This adds a way to specify which devices
belong on which bus.

i.e.,
device pci 14.3 on  # - D14F3 bridge
	device espi 0 on
		chip ec/google/chromeec
			device pnp 0c09.0 on end
		end
	end
	device lpc 0 on
	end
end

BUG=b:154445472
TEST=Built trembyle and saw static.c contained the espi bus.

Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: I0c2f40813c05680f72e5f30cbb13617e8f994841
Reviewed-on: https://review.coreboot.org/c/coreboot/+/41099
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

util/sconfig/sconfig.tab.h_shipped

@@ -81,7 +81,9 @@ extern int yydebug;
     GENERIC = 287,
     SPI = 288,
     USB = 289,
-    MMIO = 290
+    MMIO = 290,
+    LPC = 291,
+    ESPI = 292
   };
 #endif