utils.memory: use the new DataSize object

There's a new DataSize object in avocado.utils.datastructures. Let's
remove the redundant code and just use the DataSize object.
Signed-off-by: NAmador Pahim <apahim@redhat.com>

avocado/utils/memory.py

@@ -26,6 +26,7 @@ import logging
 from . import process
 from . import genio
 from . import wait
+from .data_structures import DataSize
 
 
 class MemoryError(Exception):
@@ -414,38 +415,13 @@ def get_thp_value(feature):
         return value
 
 
-class _MemInfoItem(object):
+class _MemInfoItem(DataSize):
     """
     Representation of one item from /proc/meminfo
     """
     def __init__(self, name):
+        super(_MemInfoItem, self).__init__('%sk' % read_from_meminfo(name))
         self.name = name
-        self.__multipliers = {'b': 1,  # 2**0
-                              'kb': 1024,  # 2**10
-                              'mb': 1048576,  # 2**20
-                              'gb': 1073741824,  # 2**30
-                              'tb': 1099511627776}  # 2**40
-
-    def __getattr__(self, attr):
-        """
-        Creates one extra attribute per available conversion unit,
-        which will return the converted value.
-        """
-        if attr not in self.__multipliers:
-            raise AttributeError('Attribute %s does not exist.' % attr)
-        return self.value * 1024 / self.__multipliers[attr]
-
-    def __dir__(self):
-        """
-        Makes the extra attributes visible when calling dir().
-        """
-        listing = dir(type(self)) + list(self.__dict__.keys())
-        listing.extend(['%s' % item for item in self.__multipliers])
-        return listing
-
-    @property
-    def value(self):
-        return read_from_meminfo(self.name)
 
 
 class MemInfo(object):