tools/osbuild-mpp: handle corner case in mpp-format-int

If you do math in mpp-format-int it could end up getting converted
to a float. Of course if you end up with a decimal value that isn't
`.0` that's a problem for an int, but if it is `.0` let's handle it
gracefully.

For example, math like this could end up with a value with `.0`:

  mpp-format-int: "{bios_boot_size_mb * 1024 * 1024 / sector_size_bytes}"

tools/osbuild-mpp

@@ -1259,6 +1259,11 @@ class ManifestFile:
                 sys.exit(1)
 
             if res_type == "int":
+                # If the value ends with '.0' it could be because of
+                # some math that ended up converting the value to a
+                # float. Just trim it off in that case.
+                if res.endswith('.0'):
+                    res = res.strip('.0')
                 res = int(res)
             elif res_type == "json":
                 res = json.loads(res)