ARM: EXYNOS: Skip C1 cpuidle state for exynos5440

This patch skips the deep C1(AFTR -Arm off top running) state for
exynos5440 SoC as this soc does not support this state. The cpu's
only allows the basic C0 state.
The C1 state is filtered by re-initialising the driver state_count
value to 1.

Suggested-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>