Allow sigreturn syscall

This is used on some 32 bit architectures, eg x86

Signed-off-by: Justin Cormack <justin.cormack@unikernel.com>

daemon/execdriver/native/seccomp_default.go

@@ -1308,6 +1308,11 @@ var defaultSeccompProfile = &configs.Seccomp{
 			Action: configs.Allow,
 			Args:   []*configs.Arg{},
 		},
+		{
+			Name:   "sigreturn",
+			Action: configs.Allow,
+			Args:   []*configs.Arg{},
+		},
 		{
 			Name:   "socket",
 			Action: configs.Allow,