thunderbolt: dma_test: Drop unnecessary include

It seems <linux/acpi.h> is not actually needed in this driver so we can
drop it.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

drivers/thunderbolt/dma_test.c

@@ -7,7 +7,6 @@
  *	    Mika Westerberg <mika.westerberg@linux.intel.com>
  */
 
-#include <linux/acpi.h>
 #include <linux/completion.h>
 #include <linux/debugfs.h>
 #include <linux/module.h>