ARM: OMAP3: cpuidle - simplify next_valid_state

Simplify the indentation by removing the useless 'else' statement.
Remove the first loop for the 'idx' search as we have it already
with the 'index' passed as parameter.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Jean Pihet <j-pihet@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>