[PATCH bpf] selftests/bpf: fix unused attribute usage in subprogs_unused test

[Andrii Nakryiko]

Correct attribute name is "unused". maybe_unused is a C++17 addition.
This patch fixes compilation warning during selftests compilation.

Fixes: 197afc631413 ("libbpf: Don't attempt to load unused subprog as an 
entry-point BPF program")
Signed-off-by: Andrii Nakryiko <and...@kernel.org>
---
 tools/testing/selftests/bpf/progs/test_subprogs_unused.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/bpf/progs/test_subprogs_unused.c 
b/tools/testing/selftests/bpf/progs/test_subprogs_unused.c
index 75d975f8cf90..bc49e050d342 100644
--- a/tools/testing/selftests/bpf/progs/test_subprogs_unused.c
+++ b/tools/testing/selftests/bpf/progs/test_subprogs_unused.c
@@ -4,12 +4,12 @@
 
 const char LICENSE[] SEC("license") = "GPL";
 
-__attribute__((maybe_unused)) __noinline int unused1(int x)
+__attribute__((unused)) __noinline int unused1(int x)
 {
        return x + 1;
 }
 
-static __attribute__((maybe_unused)) __noinline int unused2(int x)
+static __attribute__((unused)) __noinline int unused2(int x)
 {
        return x + 2;
 }
-- 
2.24.1