UPSTREAM: cgroup: Move cgroup_parse_float() implementation out of CONFIG_SYSFS

a5e112e6424a ("cgroup: add cgroup_parse_float()") accidentally added
cgroup_parse_float() inside CONFIG_SYSFS block.  Move it outside so
that it doesn't cause failures on !CONFIG_SYSFS builds.

Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: a5e112e6424a ("cgroup: add cgroup_parse_float()")
(cherry picked from commit 38cf3a687f5827fcfc81cbc433ef5822693a49c1)
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Icbd35d6b73b2f7d05a23ad84880c447a6035fa11