msm: SSR: Consolidate loops during restart

The main restart function loops over the restart list many times
and repeats the same looping logic each time. Extract that loop
into a function and call it with a function reflecting what each
loop is doing: shutdown, ramdump, powerup, and all the notifiers
before and after.

Change-Id: Ic448367f708e9ddee151511df2be3773e9d4f63f
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>