Revert "lenovo/t400/4.5-1564-g6fa36c9c2c-dirty/2017-04-16T13_28_27Z"

This reverts commit e5454d36ca2f96e452a228db9a1485bff2e8f32e.

The commit in question deletes a lot of unrelated files, and needs to be
reverted.
diff --git a/lenovo/x60/4.5-709-gc2973d1/2016-12-23T03_54_55Z/rom_checksum.txt b/lenovo/x60/4.5-709-gc2973d1/2016-12-23T03_54_55Z/rom_checksum.txt
new file mode 100644
index 0000000..bf647f8
--- /dev/null
+++ b/lenovo/x60/4.5-709-gc2973d1/2016-12-23T03_54_55Z/rom_checksum.txt
@@ -0,0 +1 @@
+34b0c8c53e5ab2acb8ca766cd93f5f79 *build/coreboot.rom