style: Fix PEP8 blank lines issues in Python files

Done with `autopep8 --select=E3,W3`, fixes:

- E301 - Add missing blank line.
- E302 - Add missing 2 blank lines.
- E303 - Remove extra blank lines.
- E304 - Remove blank line following function decorator.
- E309 - Add missing blank line.
- W391 - Remove trailing blank lines.

platform/haiku/detect.py

@@ -1,12 +1,15 @@
 import os
 import sys
 
+
 def is_active():
     return True
 
+
 def get_name():
     return "Haiku"
 
+
 def can_build():
     if (os.name != "posix"):
         return False
@@ -16,15 +19,18 @@ def can_build():
 
     return True
 
+
 def get_opts():
     return [
         ('debug_release', 'Add debug symbols to release version', 'no')
     ]
 
+
 def get_flags():
     return [
     ]
 
+
 def configure(env):
     is64 = sys.maxsize > 2**32