ACPI: OSL: Add missing __acquires/__releases annotations

Sparse reports a warnings at acpi_os_acquire_lock() and
acpi_os_release_lock():

warning: context imbalance in acpi_os_acquire_lock() - unexpected unlock

warning: context imbalance in acpi_os_release_lock() - unexpected unlock

which result from missing __acquires/__releases annotations.

Add the annotations as appropriate to get rid of the warnings.

Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
[ rjw: Two patches merged into one, subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/osl.c

@@ -1598,6 +1598,7 @@ void acpi_os_delete_lock(acpi_spinlock handle)
  */
 
 acpi_cpu_flags acpi_os_acquire_lock(acpi_spinlock lockp)
+	__acquires(lockp)
 {
 	acpi_cpu_flags flags;
 	spin_lock_irqsave(lockp, flags);
@@ -1609,6 +1610,7 @@ acpi_cpu_flags acpi_os_acquire_lock(acpi_spinlock lockp)
  */
 
 void acpi_os_release_lock(acpi_spinlock lockp, acpi_cpu_flags flags)
+	__releases(lockp)
 {
 	spin_unlock_irqrestore(lockp, flags);
 }