pstore: Make "part" unsigned

We'll never have a negative part, so just make this an unsigned int.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 163bb40..49ff1de 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -67,7 +67,8 @@
 	unsigned long	size, total = 0;
 	char		*dst, *why;
 	u64		id;
-	int		hsize, part = 1;
+	int		hsize;
+	unsigned int	part = 1;
 
 	if (reason < ARRAY_SIZE(reason_str))
 		why = reason_str[reason];