isisd, lib: Fix some more compiler warnings

A couple compiler warnings snuck in from the last
round of work being looked at.  This cleans them up

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/log.c b/lib/log.c
index e376205d..0914bf84 100644
--- a/lib/log.c
+++ b/lib/log.c
@@ -1036,7 +1036,7 @@ zlog_hexdump (void *mem, unsigned int len) {
               if (j >= len) /* end of block, not really printing */
                 s += sprintf(s, " ");
 
-              else if(isprint(((char*)mem)[j])) /* printable char */
+              else if(isprint((int)((char*)mem)[j])) /* printable char */
                 s += sprintf(s, "%c", 0xFF & ((char*)mem)[j]);
 
               else /* other char */