efi_driver: provide SBI based runtime system reset

On RISC-V systems system the Supervisory Binary Interface provides system
reset and poweroff. Use it at EFI runtime.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig
index db5571d..a7c3e05 100644
--- a/lib/efi_loader/Kconfig
+++ b/lib/efi_loader/Kconfig
@@ -366,7 +366,7 @@
 	bool
 	default y
 	depends on ARCH_BCM283X || FSL_LAYERSCAPE || PSCI_RESET || \
-		   SANDBOX || SYSRESET_X86
+		   SANDBOX || SYSRESET_SBI || SYSRESET_X86
 
 config EFI_GRUB_ARM32_WORKAROUND
 	bool "Workaround for GRUB on 32bit ARM"