ANDROID: vendor_hooks: Guard cgroup struct with CONFIG_CGROUPS

See commit 573c7f06 ("ANDROID: Guard hooks with their CONFIG_
options"). Needed to do CGROUPS as well due to cgroup_subsys definition
being guarded by CONFIG_CGROUPS in include/linux/cgroup-defs.h.

Bug: 240404657
Change-Id: Ie51f053a9e82ef8d7d1c149374ac02608717429d
Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>