cmd: terminate efidebug test bootmgr early on error

If efi_bootmgr_load() fails, there is no point in trying to start an image
that has not been loaded.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
diff --git a/cmd/efidebug.c b/cmd/efidebug.c
index d1f86e7..c2c525f 100644
--- a/cmd/efidebug.c
+++ b/cmd/efidebug.c
@@ -1397,6 +1397,8 @@
 
 	ret = efi_bootmgr_load(&image, &load_options);
 	printf("efi_bootmgr_load() returned: %ld\n", ret & ~EFI_ERROR_MASK);
+	if (ret != EFI_SUCCESS)
+		return CMD_RET_SUCCESS;
 
 	/* We call efi_start_image() even if error for test purpose. */
 	ret = EFI_CALL(efi_start_image(image, &exit_data_size, &exit_data));