Remove unused dict BYTE_MULTIPLIERS

Dict BYTE_MULTIPLIERS in ironic/common/utils.py isn't used
anywhere, and ironic/openstack/common/strutils.py includes
this dict, So we can use the one in oslo if we need. It's
safe to remove it now.

Change-Id: Iff96369057741c9a5b97fe44be7e6dd77c21ee82

ironic/common/utils.py

@@ -54,16 +54,6 @@ CONF.register_opts(utils_opts)
 
 LOG = logging.getLogger(__name__)
 
-# Used for looking up extensions of text
-# to their 'multiplied' byte amount
-BYTE_MULTIPLIERS = {
-    '': 1,
-    't': 1024 ** 4,
-    'g': 1024 ** 3,
-    'm': 1024 ** 2,
-    'k': 1024,
-}
-
 
 def _get_root_helper():
     return 'sudo ironic-rootwrap %s' % CONF.rootwrap_config