maint: fix printf format for signed integers

With GCC 5 and the newly added warnings from gnulib, ensure the
correct signed integer is passed for the printf format,
to avoid -Werror=format= failures.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/dd.c b/src/dd.c
index 321b096d4..6b09bc645 100644
--- a/src/dd.c
+++ b/src/dd.c
@@ -1685,7 +1685,7 @@ skip_via_lseek (char const *filename, int fdesc, off_t offset, int whence)
         error (0, 0, _("warning: working around lseek kernel bug for file "
                        "(%s)\n  of mt_type=0x%0lx -- "
                        "see <sys/mtio.h> for the list of types"),
-               filename, s2.mt_type);
+               filename, s2.mt_type + 0Lu);
       errno = 0;
       new_position = -1;
     }