mn50: fix usb_update

Add support for update related vendor commands in mn50 by relocating
relevant code from board/cr50 to chip/g.

BUG=b:36910757
BRANCH=None
TEST=./extra/usb_updater/usb_updater -d 18d1:502a build/mn50/ec.bin

Change-Id: Iec0fe5585b5b6eb099f9254dfb0e5b02d5106abc
Reviewed-on: https://chromium-review.googlesource.com/537999
Commit-Ready: Nick Sanders <nsanders@chromium.org>
Tested-by: Nick Sanders <nsanders@chromium.org>
Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>

board/cr50/build.mk

@@ -43,12 +43,10 @@ board-y += tpm2/hash_data.o
 board-y += tpm2/hkdf.o
 board-y += tpm2/manufacture.o
 board-y += tpm2/platform.o
-board-y += tpm2/post_reset.o
 board-y += tpm2/rsa.o
 board-y += tpm2/stubs.o
 board-y += tpm2/tpm_state.o
 board-y += tpm2/trng.o
-board-y += tpm2/upgrade.o
 board-y += tpm_nvmem_read.o
 board-y += wp.o
 

board/mn50/board.c

@@ -304,7 +304,11 @@ DECLARE_SAFE_CONSOLE_COMMAND(socket, command_socket,
 			     "[enable|disable]",
 			     "Activate and deactivate socket");
 
-
+void post_reboot_request(void)
+{
+	/* This will never return. */
+	system_reset(SYSTEM_RESET_MANUALLY_TRIGGERED | SYSTEM_RESET_HARD);
+}
 
 /* Determine key type based on the key ID. */
 static const char *key_type(uint32_t key_id)

chip/g/build.mk

@@ -66,7 +66,7 @@ chip-y+= pmu.o
 chip-y+= trng.o
 chip-y+= runlevel.o
 chip-$(CONFIG_USB_FW_UPDATE)+= usb_upgrade.o
-chip-$(CONFIG_NON_HC_FW_UPDATE)+= upgrade_fw.o
+chip-$(CONFIG_NON_HC_FW_UPDATE)+= upgrade_fw.o post_reset.o upgrade.o
 chip-$(CONFIG_SPS)+= sps.o
 chip-$(CONFIG_TPM_SPS)+=sps_tpm.o
 chip-$(CONFIG_WATCHDOG)+=watchdog.o