ARM:OMAP3: Smartreflex disable/enable fix

Smartreflex modules have to be disabled when device enters WFI.
Previously only suspend idle path had these calls. By moving the
disable/enable calls to omap_sram_idle, all idle paths will be covered.

Signed-off-by: Kalle Jokiniemi <ext-kalle.jokiniemi@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>