vboot: Add new function for logging recovery mode switches

BUG=chrome-os-partner:59352
BRANCH=None
TEST=Compiles successfully

Change-Id: I87cd675ea45a8b05a178cf64119bf5f9d8d218ca
Signed-off-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: https://review.coreboot.org/17408
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/include/bootmode.h

@@ -24,6 +24,7 @@ int get_developer_mode_switch(void);
 int get_recovery_mode_switch(void);
 int get_recovery_mode_retrain_switch(void);
 int clear_recovery_mode_switch(void);
+void log_recovery_mode_switch(void);
 int get_wipeout_mode_switch(void);
 int get_lid_switch(void);
 

src/vboot/vboot_handoff.c

@@ -153,6 +153,10 @@ void vboot_fill_handoff(void)
 	/* needed until we finish transtion to vboot2 for kernel verification */
 	fill_vboot_handoff(vh, sd);
 
+
+	/* Log the recovery mode switches if required, before clearing them. */
+	log_recovery_mode_switch();
+
 	/*
 	 * The recovery mode switch is cleared (typically backed by EC) here
 	 * to allow multiple queries to get_recovery_mode_switch() and have

src/vendorcode/google/chromeos/chromeos.c

@@ -33,3 +33,8 @@ int __attribute__((weak)) get_sw_write_protect_state(void)
 	// Can be implemented by a platform / mainboard
 	return 0;
 }
+
+void __attribute__((weak)) log_recovery_mode_switch(void)
+{
+	// Weak implementation. Nothing to do.
+}