LibELF: Disallow the DynamicLinker from linking a static-pie ELF object

The dynamic loader can't reasonably run static-pie ELF. static-pie ELFs
might run executable code that invokes syscalls outside of the defined
syscall memory executable (code) region security measure we implement.

Known examples of static-pie ELF objects are ELF packers, and the actual
system-provided dynamic loader itself.

Userland/Libraries/LibELF/DynamicObject.cpp

@@ -183,6 +183,7 @@ void DynamicObject::parse()
         case DT_DEBUG:
             break;
         case DT_FLAGS_1:
+            m_is_pie = true;
             break;
         case DT_NEEDED:
             // We handle these in for_each_needed_library