mainboard/ocp/monolake: Give the BMC time to startup

Set bmc_boot_timeout and wait_for_bmc to give the BMC more time to respond
before coreboot times out and moves on. Passes IPMI BMC selftest.

Change-Id: I310a08b8c134cf839381675ade2fe7deee9b1909
Signed-off-by: Marc Jones <marcj303@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/55770
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Jay Talbott <JayTalbott@sysproconsulting.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/ocp/monolake/devicetree.cb

@@ -14,6 +14,9 @@ chip soc/intel/fsp_broadwell_de
 			chip drivers/ipmi		# BMC KCS
 				device pnp ca2.0 on end
 				register "bmc_i2c_address" = "0x20"
+				# On cold boot it takes a while for the BMC to start the IPMI service
+				register "wait_for_bmc" = "1"
+				register "bmc_boot_timeout" = "60"
 			end
 		end # LPC Bridge
 		device pci 1f.2 on end # SATA Controller