maint: fix assumption typo

Fix a typo I introduced in my August 2021 signal handling fixes.
Problem reported by Sam James (Bug#60457).
* src/util.c (xsigismember): Don’t assume sigismember cannot return 0.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/util.c b/src/util.c
index d2fd5ca..e4d7240 100644
--- a/src/util.c
+++ b/src/util.c
@@ -202,7 +202,7 @@ xsigismember (sigset_t const *set, int sig)
   int mem = sigismember (set, sig);
   if (mem < 0)
     pfatal_with_name ("sigismember");
-  assume (mem == 1);
+  assume (mem <= 1);
   return mem;
 }