Add safety margin on truncation

It seems that Intel ME requires some data after the last valid byte, as
truncating the image just after the last byte does not work.
For now this "safety margin" has been set to 4 blocks (16 kB).

me_cleaner.py

@@ -24,6 +24,7 @@
 
 
 min_ftpr_offset = 0x400
+spared_blocks = 4
 unremovable_modules = ("BUP", "ROMP")
 
 
@@ -469,9 +470,10 @@ def relocate_partition(f, me_start, me_end, partition_header_offset,
                             ftpr_offset = new_ftpr_offset
 
                         end_addr = (end_addr // 0x1000 + 1) * 0x1000
+                        end_addr += spared_blocks * 0x1000
 
-                        print("The ME minimum size is {0} bytes ({0:#x} bytes)"
-                              .format(end_addr - me_start))
+                        print("The ME minimum size should be {0} bytes "
+                              "({0:#x} bytes)".format(end_addr - me_start))
 
                         if me_start > 0:
                             print("The ME region can be reduced up to:\n"