ACPI: Remove unnecessary from/to-void* and to-void casts in drivers/acpi

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 068fe4f..2ed2d70 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -569,7 +569,7 @@
 	struct acpi_os_dpc *dpc = NULL;
 
 
-	dpc = (struct acpi_os_dpc *)context;
+	dpc = context;
 	if (!dpc) {
 		printk(KERN_ERR PREFIX "Invalid (NULL) context\n");
 		return;
@@ -1060,7 +1060,7 @@
 
 acpi_status acpi_os_purge_cache(acpi_cache_t * cache)
 {
-	(void)kmem_cache_shrink(cache);
+	kmem_cache_shrink(cache);
 	return (AE_OK);
 }