selftests/seccomp: Use bitwise instead of arithmetic operator for flags

This silences the following coccinelle warning:

"WARNING: sum of probable bitmasks, consider |"

tools/testing/selftests/seccomp/seccomp_bpf.c:3131:17-18: WARNING: sum of probable bitmasks, consider |
tools/testing/selftests/seccomp/seccomp_bpf.c:3133:18-19: WARNING: sum of probable bitmasks, consider |
tools/testing/selftests/seccomp/seccomp_bpf.c:3134:18-19: WARNING: sum of probable bitmasks, consider |
tools/testing/selftests/seccomp/seccomp_bpf.c:3135:18-19: WARNING: sum of probable bitmasks, consider |

Fixes: 6a21cc50 ("seccomp: add a return code to trap to userspace")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Link: https://lore.kernel.org/r/1586924101-65940-1-git-send-email-zou_wei@huawei.comSigned-off-by: Kees Cook <keescook@chromium.org>

tools/testing/selftests/seccomp/seccomp_bpf.c

@@ -3173,11 +3173,11 @@ TEST(get_metadata)
 static int user_notif_syscall(int nr, unsigned int flags)
 {
 	struct sock_filter filter[] = {
-		BPF_STMT(BPF_LD+BPF_W+BPF_ABS,
+		BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
 			offsetof(struct seccomp_data, nr)),
-		BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, nr, 0, 1),
-		BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_USER_NOTIF),
-		BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_ALLOW),
+		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, nr, 0, 1),
+		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_USER_NOTIF),
+		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 	};
 
 	struct sock_fprog prog = {