m6pack: Fix harmless -Werror=format-security build error.

make[2]: Entering directory '/home/ralf/src/ax25/ax25-tools/6pack'
gcc -DHAVE_CONFIG_H -I. -I..  -DAX25_SYSCONFDIR=\""/usr/local/etc/ax25/"\" -DAX25_LOCALSTATEDIR=\""/usr/local/var/ax25/"\"   -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -MT m6pack.o -MD -MP -MF .deps/m6pack.Tpo -c -o m6pack.o m6pack.c
m6pack.c: In function ‘main’:
m6pack.c:446:4: error: format not a string literal and no format arguments [-Werror=format-security]
    fprintf(stderr, usage_string);
    ^
m6pack.c:452:3: error: format not a string literal and no format arguments [-Werror=format-security]
   fprintf(stderr, usage_string);
   ^
m6pack.c:457:3: error: format not a string literal and no format arguments [-Werror=format-security]
   fprintf(stderr, usage_string);
   ^
cc1: some warnings being treated as errors
Makefile:384: recipe for target 'm6pack.o' failed
make[2]: *** [m6pack.o] Error 1
make[2]: Leaving directory '/home/ralf/src/ax25/ax25-tools/6pack'

The string are constants in the application code itself so no security
issue.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/6pack/m6pack.c b/6pack/m6pack.c
index e698ef3..5b63801 100644
--- a/6pack/m6pack.c
+++ b/6pack/m6pack.c
@@ -443,18 +443,18 @@ int main(int argc, char *argv[])
 			return 1;
 		case ':':
 		case '?':
-			fprintf(stderr, usage_string);
+			fprintf(stderr, "%s", usage_string);
 			return 1;
 		}
 	}
 
 	if ((argc - optind) < 2 && ptmxdevices == 0) {
-		fprintf(stderr, usage_string);
+		fprintf(stderr, "%s", usage_string);
 		return 1;
 	}
 
 	if ((argc - optind) < 1 && ptmxdevices > 0) {
-		fprintf(stderr, usage_string);
+		fprintf(stderr, "%s", usage_string);
 		return 1;
 	}