main: suppress -Werror=unused-resultHEADmaster

gcc 14.2 + glibc 2.40 produces this warning, converted to an error,
which fails the build.

	setup.c: In function ‘setup_interactively’:
	setup.c:149:32: error: ignoring return value of ‘fgets’ declared with attribute ‘warn_unused_result’ [-Werror=unused-result]
	  149 |                         (void) fgets(buf, sizeof(buf), stdin);
	      |                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	main.c: In function ‘print_setup_as_args’:
	main.c:454:24: error: ignoring return value of ‘fgets’ declared with attribute ‘warn_unused_result’ [-Werror=unused-result]
	  454 |                 (void) fgets(buf, sizeof(buf), stdin);
	      |                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

1 files changed, 4 insertions, 1 deletions

diff --git a/src/main.c b/src/main.c
index 28f897f..e4b0cbc 100644
--- a/src/main.c
+++ b/src/main.c
@@ -451,7 +451,10 @@ static int print_setup_as_args(setup_t *setup, int wait)
 		if (r < 0)
 			goto _out_video;
 
-		(void) fgets(buf, sizeof(buf), stdin);
+		if (fgets(buf, sizeof(buf), stdin) == NULL) {
+			r = -EBADF;
+			goto _out_video;
+		}
 	}
 
 _out_video: