[PATCH bpf-next] samples/bpf: hbm: Fix compile error about fallthrough marking

[Rong Tao]

From: Rong Tao <rongtao@xxxxxxxx>

commit f7a858bffcdd("tools: Rename __fallthrough to fallthrough") rename
macro __fallthrough to fallthrough, commit 4b7ef71ac977("bpftool: Replace
"__fallthrough" by a comment to address merge conflict") use comments to
replace __fallthrough, here we can use fallthrough directly.

Compiling samples/bpf hits an error related to fallthrough marking:
    ...
    CC  samples/bpf/hbm.o
    linux/samples/bpf/hbm.c: In function ‘main’:
    linux/samples/bpf/hbm.c:501:25: error: ‘__fallthrough’ undeclared
    (first use in this function); did you mean ‘fallthrough’?
    501 |                         __fallthrough;
        |                         ^~~~~~~~~~~~~
        |                         fallthrough

Signed-off-by: Rong Tao <rongtao@xxxxxxxx>
---
 samples/bpf/hbm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/samples/bpf/hbm.c b/samples/bpf/hbm.c
index 6448b7826107..7ddf25e9d098 100644
--- a/samples/bpf/hbm.c
+++ b/samples/bpf/hbm.c
@@ -498,7 +498,7 @@ int main(int argc, char **argv)
 					"Option -%c requires an argument.\n\n",
 					optopt);
 		case 'h':
-			__fallthrough;
+			fallthrough;
 		default:
 			Usage();
 			return 0;
-- 
2.39.1