mb/google/brox/var/brox: increase PsysPmax from 21.5W to 208W

According to Brox HW design, the PsysPmax is supposed to be 208W.
This patch changes PsysPmax setting from 21.5W to 208W.

Change-Id: I43f4b00a54dc0dfe6bd690492f9ef92698c9b903
Signed-off-by: Lawrence Chang <lawrence.chang@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/82185
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Shelley Chen <shchen@google.com>

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

@@ -28,6 +28,7 @@ fw_config
 end
 
 chip soc/intel/alderlake
+	register "platform_pmax" = "208"
 	device domain 0 on
 		device ref dtt on
 			chip drivers/intel/dptf