[PATCH] seccomp.sh: Silence stty errors

[Michal Privoznik <mprivozn@redhat.com>]

When printing list of allowed syscalls the width of terminal is
obtained for nicer output (see commit below). The width is
obtained by running 'stty'. While this works when building from a
console, it doesn't work during rpmbuild/emerge/.. as stdout is
usually not a console but a logfile and stdin is usually
/dev/null or something. This results in stty reporting errors
like this:

  stty: 'standard input': Inappropriate ioctl for device

Redirect stty's stderr to /dev/null to silence it.

Fixes: 712ca3235329b049bf9a4e481ba38a4c64768e8b
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
---

I've noticed the error when running emerge on my local system, but then
also found it on a recent koji build:

https://kojipkgs.fedoraproject.org//packages/passt/0%5E20250217.ga1e48a0/2.fc41/data/logs/x86_64/build.log

 seccomp.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/seccomp.sh b/seccomp.sh
index 4c521ae..a7bc417 100755
--- a/seccomp.sh
+++ b/seccomp.sh
@@ -255,7 +255,7 @@ for __p in ${__profiles}; do
 	__calls="${__calls} ${EXTRA_SYSCALLS:-}"
 	__calls="$(filter ${__calls})"
 
-	cols="$(stty -a | sed -n 's/.*columns \([0-9]*\).*/\1/p' || :)" 2>/dev/null
+	cols="$(stty -a 2>/dev/null | sed -n 's/.*columns \([0-9]*\).*/\1/p' || :)" 2>/dev/null
 	case $cols in [0-9]*) col_args="-w ${cols}";; *) col_args="";; esac
 	echo "seccomp profile ${__p} allows: ${__calls}" | tr '\n' ' ' | fmt -t ${col_args}
 
-- 
@@ -255,7 +255,7 @@ for __p in ${__profiles}; do
 	__calls="${__calls} ${EXTRA_SYSCALLS:-}"
 	__calls="$(filter ${__calls})"
 
-	cols="$(stty -a | sed -n 's/.*columns \([0-9]*\).*/\1/p' || :)" 2>/dev/null
+	cols="$(stty -a 2>/dev/null | sed -n 's/.*columns \([0-9]*\).*/\1/p' || :)" 2>/dev/null
 	case $cols in [0-9]*) col_args="-w ${cols}";; *) col_args="";; esac
 	echo "seccomp profile ${__p} allows: ${__calls}" | tr '\n' ' ' | fmt -t ${col_args}
 
-- 
2.45.3