PM / devfreq: Reorder fields in 'struct devfreq_dev_status'

PM / devfreq: Reorder fields in 'struct devfreq_dev_status'

Group some variables based on their sizes to reduce holes.
On x86_64, this shrinks the size of 'struct devfreq_dev_status' from 72 to
64 bytes.

This structure is used both to allocate static variables or is embedded in
some other structures. In both cases, reducing its size is nice to have.

Moreover, the whole structure now fits in a single cache line on x86_64.

Finally, it makes the order of code match the order of the above kernel
doc.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>