bpf: Fix tools and testing build.

I'm getting various build failures on sparc64.  The key is
usually that the userland tools get built 32-bit.

1) clock_gettime() is in librt, so that must be added to the link
   libraries.

2) "sizeof(x)" must be printed with "%Z" printf prefix.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

tools/testing/selftests/bpf/Makefile

@@ -11,7 +11,7 @@ ifneq ($(wildcard $(GENHDR)),)
 endif
 
 CFLAGS += -Wall -O2 -I$(APIDIR) -I$(LIBDIR) -I$(GENDIR) $(GENFLAGS) -I../../../include
-LDLIBS += -lcap -lelf
+LDLIBS += -lcap -lelf -lrt
 
 TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \
 	test_align test_verifier_log test_dev_cgroup

tools/testing/selftests/bpf/test_progs.c

@@ -351,7 +351,7 @@ static void test_bpf_obj_id(void)
 			  info_len != sizeof(struct bpf_map_info) ||
 			  strcmp((char *)map_infos[i].name, expected_map_name),
 			  "get-map-info(fd)",
-			  "err %d errno %d type %d(%d) info_len %u(%lu) key_size %u value_size %u max_entries %u map_flags %X name %s(%s)\n",
+			  "err %d errno %d type %d(%d) info_len %u(%Zu) key_size %u value_size %u max_entries %u map_flags %X name %s(%s)\n",
 			  err, errno,
 			  map_infos[i].type, BPF_MAP_TYPE_ARRAY,
 			  info_len, sizeof(struct bpf_map_info),
@@ -395,7 +395,7 @@ static void test_bpf_obj_id(void)
 			  *(int *)prog_infos[i].map_ids != map_infos[i].id ||
 			  strcmp((char *)prog_infos[i].name, expected_prog_name),
 			  "get-prog-info(fd)",
-			  "err %d errno %d i %d type %d(%d) info_len %u(%lu) jit_enabled %d jited_prog_len %u xlated_prog_len %u jited_prog %d xlated_prog %d load_time %lu(%lu) uid %u(%u) nr_map_ids %u(%u) map_id %u(%u) name %s(%s)\n",
+			  "err %d errno %d i %d type %d(%d) info_len %u(%Zu) jit_enabled %d jited_prog_len %u xlated_prog_len %u jited_prog %d xlated_prog %d load_time %lu(%lu) uid %u(%u) nr_map_ids %u(%u) map_id %u(%u) name %s(%s)\n",
 			  err, errno, i,
 			  prog_infos[i].type, BPF_PROG_TYPE_SOCKET_FILTER,
 			  info_len, sizeof(struct bpf_prog_info),
@@ -463,7 +463,7 @@ static void test_bpf_obj_id(void)
 		      memcmp(&prog_info, &prog_infos[i], info_len) ||
 		      *(int *)prog_info.map_ids != saved_map_id,
 		      "get-prog-info(next_id->fd)",
-		      "err %d errno %d info_len %u(%lu) memcmp %d map_id %u(%u)\n",
+		      "err %d errno %d info_len %u(%Zu) memcmp %d map_id %u(%u)\n",
 		      err, errno, info_len, sizeof(struct bpf_prog_info),
 		      memcmp(&prog_info, &prog_infos[i], info_len),
 		      *(int *)prog_info.map_ids, saved_map_id);
@@ -509,7 +509,7 @@ static void test_bpf_obj_id(void)
 		      memcmp(&map_info, &map_infos[i], info_len) ||
 		      array_value != array_magic_value,
 		      "check get-map-info(next_id->fd)",
-		      "err %d errno %d info_len %u(%lu) memcmp %d array_value %llu(%llu)\n",
+		      "err %d errno %d info_len %u(%Zu) memcmp %d array_value %llu(%llu)\n",
 		      err, errno, info_len, sizeof(struct bpf_map_info),
 		      memcmp(&map_info, &map_infos[i], info_len),
 		      array_value, array_magic_value);