Introduce DL_LOOKUP_FOR_RELOCATE flag for _dl_lookup_symbol_x

This will allow changes in dependency processing during non-lazy
binding, for more precise processing of NODELETE objects: During
initial relocation in dlopen, the fate of NODELETE objects is still
unclear, so objects which are depended upon by NODELETE objects
cannot immediately be marked as NODELETE.

elf/dl-reloc.c

@@ -244,7 +244,8 @@ _dl_relocate_object (struct link_map *l, struct r_scope_elem *scope[],
 	       v = (version);						      \
 	     _lr = _dl_lookup_symbol_x (strtab + (*ref)->st_name, l, (ref),   \
 					scope, v, _tc,			      \
-					DL_LOOKUP_ADD_DEPENDENCY, NULL);      \
+					DL_LOOKUP_ADD_DEPENDENCY	      \
+					| DL_LOOKUP_FOR_RELOCATE, NULL);      \
 	     l->l_lookup_cache.ret = (*ref);				      \
 	     l->l_lookup_cache.value = _lr; }))				      \
      : l)

sysdeps/generic/ldsodefs.h

@@ -914,6 +914,9 @@ enum
     DL_LOOKUP_RETURN_NEWEST = 2,
     /* Set if dl_lookup* called with GSCOPE lock held.  */
     DL_LOOKUP_GSCOPE_LOCK = 4,
+    /* Set if dl_lookup is called for non-lazy relocation processing
+       from _dl_relocate_object in elf/dl-reloc.c.  */
+    DL_LOOKUP_FOR_RELOCATE = 8,
   };
 
 /* Lookup versioned symbol.  */