buildhistory_analysis: correctly handle whitespace when splitting lists

Don't specify any argument to the split() function when handling changes
to list type variables (e.g. PACKAGES) so that the values are split by
any whitespace and only split once for a block of multiple whitespace
characters.

(From OE-Core rev: 15ad5d2c0e92fefdbb7c0cf064134b1cabfd84ac)

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oe/buildhistory_analysis.py

@@ -34,8 +34,8 @@ class ChangeRecord:
 
     def __str__(self):
         if self.fieldname in list_fields:
-            aitems = self.oldvalue.split(' ')
-            bitems = self.newvalue.split(' ')
+            aitems = self.oldvalue.split()
+            bitems = self.newvalue.split()
             removed = list(set(aitems) - set(bitems))
             added = list(set(bitems) - set(aitems))
             return '%s: %s:%s%s' % (self.path, self.fieldname, ' removed "%s"' % ' '.join(removed) if removed else '', ' added "%s"' % ' '.join(added) if added else '')