OMAP3: PM: CPUidle: base driver and support for C1-C2

Basic CPUidle driver for OMAP3 with deepest sleep state supported
being MPU CSWR.

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

arch/arm/mach-omap2/pm34xx.c

@@ -318,7 +318,7 @@ static void restore_table_entry(void)
 	restore_control_register(control_reg_value);
 }
 
-static void omap_sram_idle(void)
+void omap_sram_idle(void)
 {
 	/* Variable to tell what needs to be saved and restored
 	 * in omap_sram_idle*/
@@ -1101,7 +1101,9 @@ static int __init omap3_pm_init(void)
 	suspend_set_ops(&omap_pm_ops);
 #endif /* CONFIG_SUSPEND */
 
+#ifndef CONFIG_CPU_IDLE
 	pm_idle = omap3_pm_idle;
+#endif
 
 	pwrdm_add_wkdep(neon_pwrdm, mpu_pwrdm);
 	/*