sysd-rules: Cut down the number of rtld-% pattern rules

rtld only needs shared objects, so the other patterns are pointless and
significantly increase the work make has to perform while identifying
which pattern rule to apply.

scripts/sysd-rules.awk

@@ -50,6 +50,10 @@ BEGIN {
         split(pattern, td, ":");
         target_pattern = td[1];
         dep_pattern = td[2];
+        # rtld objects are always PIC.
+        if (target_pattern ~ /^rtld/ && o != ".os") {
+            continue;
+        }
         if (target_pattern == "%") {
           command_suffix = "";
         } else {