efi_loader: implement SetWatchdogTimer

The watchdog is initialized with a 5 minute timeout period.
It can be reset by SetWatchdogTimer.
It is stopped by ExitBoottimeServices.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

include/efi_loader.h

@@ -163,6 +163,8 @@ int efi_disk_register(void);
 int efi_gop_register(void);
 /* Called by bootefi to make the network interface available */
 int efi_net_register(void);
+/* Called by bootefi to make the watchdog available */
+int efi_watchdog_register(void);
 /* Called by bootefi to make SMBIOS tables available */
 void efi_smbios_register(void);
 
@@ -171,6 +173,8 @@ efi_fs_from_path(struct efi_device_path *fp);
 
 /* Called by networking code to memorize the dhcp ack package */
 void efi_net_set_dhcp_ack(void *pkt, int len);
+/* Called by efi_set_watchdog_timer to reset the timer */
+efi_status_t efi_set_watchdog(unsigned long timeout);
 
 /* Called from places to check whether a timer expired */
 void efi_timer_check(void);