fix si_names context debugging names

I recently added a new context stack type, MULTICALL. The table
si_names[], which contains the stack type names to display with
-Dsv a new label added, "MULTICALL", but the previous label didn't
have a comma after it, so the two labels were actually being concatenated.

Spotted by Coverity

1 files changed, 1 insertions, 1 deletions

diff --git a/deb.c b/deb.c
index 4ae101d0fc..df0d60630d 100644
--- a/deb.c
+++ b/deb.c
@@ -191,7 +191,7 @@ static const char * const si_names[] = {
     "DESTROY",
     "WARNHOOK",
     "DIEHOOK",
-    "REQUIRE"
+    "REQUIRE",
     "MULTICALL"
 };
 #endif