usb: storage: Add usb_stor_dbg, reduce object size

Reduce the size of the objects by consolidating
the duplicated USB_STORAGE into a single function.

Add function usb_stor_dbg to emit debugging messages.
Always validate the format and arguments.
Reduce the number of uses of CONFIG_USB_STORAGE_DEBUG.

Reduces size of objects ~7KB when CONFIG_USB_STORAGE_DEBUG
is set.

$ size drivers/usb/storage/built-in.o*
   text	   data	    bss	    dec	    hex	filename
 140133	  55296	  70312	 265741	  40e0d	drivers/usb/storage/built-in.o.new
 147494	  55248	  70296	 273038	  42a8e	drivers/usb/storage/built-in.o.old

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/storage/isd200.c b/drivers/usb/storage/isd200.c
index 06a3d22..55571ae 100644
--- a/drivers/usb/storage/isd200.c
+++ b/drivers/usb/storage/isd200.c
@@ -926,10 +926,6 @@
 
 	/* loop until we detect !BSY or timeout */
 	while(1) {
-#ifdef CONFIG_USB_STORAGE_DEBUG
-		char* mstr = master_slave == ATA_ADDRESS_DEVHEAD_STD ?
-			"Master" : "Slave";
-#endif
 
 		status = isd200_action( us, ACTION_ENUM, NULL, master_slave );
 		if ( status != ISD200_GOOD )
@@ -942,9 +938,13 @@
 
 		if (!detect) {
 			if (regs[ATA_REG_STATUS_OFFSET] & ATA_BUSY) {
-				US_DEBUGP("   %s status is still BSY, try again...\n",mstr);
+				US_DEBUGP("   %s status is still BSY, try again...\n",
+					  master_slave == ATA_ADDRESS_DEVHEAD_STD ?
+					  "Master" : "Slave");
 			} else {
-				US_DEBUGP("   %s status !BSY, continue with next operation\n",mstr);
+				US_DEBUGP("   %s status !BSY, continue with next operation\n",
+					  master_slave == ATA_ADDRESS_DEVHEAD_STD ?
+					  "Master" : "Slave");
 				break;
 			}
 		}