ARM: tegra: pm: fix build error w/o PM_SLEEP

This fixes the building error when the PM_SLEEP is disabled. The fucntional
defintion of "tegra_pm_validate_suspend_mode" without "static inline"
would become a multiple definition error.
Reported-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

arch/arm/mach-tegra/pm.h

@@ -39,7 +39,7 @@ enum tegra_suspend_mode tegra_pm_validate_suspend_mode(
 				enum tegra_suspend_mode mode);
 void tegra_init_suspend(void);
 #else
-enum tegra_suspend_mode tegra_pm_validate_suspend_mode(
+static inline enum tegra_suspend_mode tegra_pm_validate_suspend_mode(
 				enum tegra_suspend_mode mode)
 {
 	return TEGRA_SUSPEND_NONE;