[PATCH iproute2] ipmacsec: fix warning on 32bit platform

[Stephen Hemminger]

On some 32 bit platforms, the printf was causing warning:
ipmacsec.c: In function ‘getattr_u64’:
ipmacsec.c:655:47: warning: format ‘%lu’ expects argument of type ‘long 
unsigned int’, but argument 3 has type ‘unsigned int’ [-Wformat=]
   fprintf(stderr, "invalid attribute length %lu\n",

Resolve by computing length as size_t first.

Signed-off-by: Stephen Hemminger <step...@networkplumber.org>
---
 ip/ipmacsec.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/ip/ipmacsec.c b/ip/ipmacsec.c
index 9b991065e483..54cd2b8c97e4 100644
--- a/ip/ipmacsec.c
+++ b/ip/ipmacsec.c
@@ -640,9 +640,11 @@ static void print_attrs(struct rtattr *attrs[])
        }
 }
 
-static __u64 getattr_u64(struct rtattr *stat)
+static __u64 getattr_u64(const struct rtattr *stat)
 {
-       switch (RTA_PAYLOAD(stat)) {
+       size_t len = RTA_PAYLOAD(stat);
+
+       switch (len) {
        case sizeof(__u64):
                return rta_getattr_u64(stat);
        case sizeof(__u32):
@@ -652,8 +654,8 @@ static __u64 getattr_u64(struct rtattr *stat)
        case sizeof(__u8):
                return rta_getattr_u8(stat);
        default:
-               fprintf(stderr, "invalid attribute length %lu\n",
-                       RTA_PAYLOAD(stat));
+               fprintf(stderr, "invalid attribute length %zu\n",
+                       len);
                exit(-1);
        }
 }
-- 
2.19.2