Staging: comedi: addi_amcc_s5933.h: sparse cleanup

Mark a variable static that does not need to be global.

Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: Frank Mori Hess <fmhess@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/comedi/drivers/addi-data/addi_amcc_s5933.h

@@ -212,7 +212,7 @@ struct pcilst_struct {
 };
 
 /* ptr to root list of all amcc devices */
-struct pcilst_struct *amcc_devices;
+static struct pcilst_struct *amcc_devices;
 
 static const int i_ADDIDATADeviceID[] = { 0x15B8, 0x10E8 };