ARM: OMAP2+: Remove unused wakeup_cpu

After commit 32d174ed ("ARM: OMAP4: MPUSS PM: remove unnecessary
shim functions for powerdomain control") this is no longer used.

The code continues execution after context restore on the same CPU,
so we can just use pm_info->pwrdm.

Cc: Merlijn Wajer <merlijn@wizzup.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Sebastian Reichel <sre@kernel.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/omap-mpuss-lowpower.c

@@ -227,7 +227,6 @@ int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
 {
 	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu);
 	unsigned int save_state = 0, cpu_logic_state = PWRDM_POWER_RET;
-	unsigned int wakeup_cpu;
 
 	if (omap_rev() == OMAP4430_REV_ES1_0)
 		return -ENXIO;
@@ -292,7 +291,6 @@ int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
 	 * secure devices, CPUx does WFI which can result in
 	 * domain transition
 	 */
-	wakeup_cpu = smp_processor_id();
 	pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
 
 	pwrdm_post_transition(NULL);