ARM: tegra: use setup_mm_for_reboot rather than explicit pgd switch

This patch changes the Tegra PM code to use the setup_mm_for_reboot
helper rather than call cpu_switch_mm directly. This keeps things like
TLB invalidation in one place.

Cc: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NStephen Warren <swarren@nvidia.com>

arch/arm/mach-tegra/pm.c

@@ -164,12 +164,7 @@ bool tegra_set_cpu_in_lp2(int phy_cpu_id)
 
 static int tegra_sleep_cpu(unsigned long v2p)
 {
-	/* Switch to the identity mapping. */
-	cpu_switch_mm(idmap_pgd, &init_mm);
-
-	/* Flush the TLB. */
-	local_flush_tlb_all();
-
+	setup_mm_for_reboot();
 	tegra_sleep_cpu_finish(v2p);
 
 	/* should never here */