python: libcgroup.pyx - fix lines, spaces lint warnings

python: libcgroup.pyx - fix lines, spaces lint warnings

Fix following spaces, lines warnings reported by Cython-lint:
- libcgroup.pyx:14:13: E222 multiple spaces after operator
- libcgroup.pyx:50:1: E302 expected 2 blank lines, found 1
- libcgroup.pyx:53:1: E302 expected 2 blank lines, found 1
- libcgroup.pyx:57:1: E302 expected 2 blank lines, found 1
- libcgroup.pyx:85:1: E305 expected 2 blank lines after class or function definition, found 1

Signed-off-by: Kamalesh Babulal <kamalesh.babulal@oracle.com>
Signed-off-by: Tom Hromatka <tom.hromatka@oracle.com>