omap_sr_probe() creates the smartreflex debug directory and its
underlying nvalue debug directory. These directories are removed in
omap_sr_remove().

Basic smartreflex functionality tested on OMAP3630 Zoom3 & OMAP4430 SDP
Signed-off-by: NAnand S Sawant <sawant@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>