debuggerd: Don't look up symbols if stab isn't found

If the symbol table isn't found during tombstone generation, we skip lookups
of addresses on the stack.

Signed-off-by: Bruce Beare <bruce.j.beare@intel.com>
Signed-off-by: Nick Kralevich <nnk@google.com>

debuggerd/symbol_table.c

diff --git a/debuggerd/symbol_table.c b/debuggerd/symbol_table.c
index e76df33..3ad08a2 100644
--- a/debuggerd/symbol_table.c
+++ b/debuggerd/symbol_table.c
@@ -83,7 +83,7 @@
             dynsym_idx = i;
         }
     }
-    if ((dynsym_idx == -1) && (sym_idx == -1)) {
+    if ((dynsym_idx == -1) || (sym_idx == -1)) {
         goto out_unmap;
     }