Staging: crystalhd: don't waste the last char of buffer

pinfo->name is a 32 char buffer.  In the original code, the last char
wasn't fully utilized.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/staging/crystalhd/crystalhd_lnx.c b/drivers/staging/crystalhd/crystalhd_lnx.c
index 9a6b650..c1ee24c 100644
--- a/drivers/staging/crystalhd/crystalhd_lnx.c
+++ b/drivers/staging/crystalhd/crystalhd_lnx.c
@@ -562,7 +562,7 @@
 		return rc;
 	}
 
-	snprintf(pinfo->name, 31, "crystalhd_pci_e:%d:%d:%d",
+	snprintf(pinfo->name, sizeof(pinfo->name), "crystalhd_pci_e:%d:%d:%d",
 		 pdev->bus->number, PCI_SLOT(pdev->devfn),
 		 PCI_FUNC(pdev->devfn));