ARM: OMAP2+: dmtimer: remove redundant sysconfig context restore

Since hwmod framework now manages sysconfig context save/restore
there is no more need to touch this register in driver. Hence,
remove restore of sysconfig register in omap_timer_restore_context.
This was causing incorrect context restore of sysconfig register.

Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>