Use own addrsize implementation (dhorak)

Anaconda doesn't built the addrsize tool used to create the file
containing size and load address for initrd.img. So we implement
its function directly in lorax.

src/pylorax/images.py

@@ -27,6 +27,7 @@ import subprocess
 import shutil
 import glob
 import collections
+import struct
 
 from base import DataHolder
 from sysutils import joinpaths, cpfile, replace
@@ -637,16 +638,13 @@ class S390(object):
             logger.info("compressing the install tree")
             self.installtree.compress(initrd, kernel, self.ctype, self.cargs)
 
-            # run addrsize
-            addrsize = joinpaths(self.installtree.root, "usr/libexec",
-                                 "anaconda", "addrsize")
-
-            cmd = [addrsize, INITRD_ADDRESS, initrd.fpath,
-                   joinpaths(self.outputroot, IMAGESDIR, "initrd.addrsize")]
-
-            p = subprocess.Popen(cmd, stdin=subprocess.PIPE,
-                                 stdout=subprocess.PIPE)
-            p.wait()
+            # create initrd.addrsize
+            addrsize = open(joinpaths(self.outputroot, IMAGESDIR,
+                                      "initrd.addrsize"), "wb")
+            addrsize_data = struct.pack(">iiii", 0, int(INITRD_ADDRESS, 16), 0,
+                                        os.stat(initrd.fpath).st_size)
+            addrsize.write(addrsize_data)
+            addrsize.close()
 
             # add kernel and initrd to .treeinfo
             kernel_arch = kernel.version.split(".")[-1]