objtool: Print data address for "!ENDBR" data warnings

When a "!ENDBR" warning is reported for a data section, objtool just
prints the text address of the relocation target twice, without giving
any clues about the location of the original data reference:

  vmlinux.o: warning: objtool: dcbnl_netdevice_event()+0x0: .text+0xb64680: data relocation to !ENDBR: dcbnl_netdevice_event+0x0

Instead, print the address of the data reference, in addition to the
address of the relocation target.

  vmlinux.o: warning: objtool: dcbnl_nb+0x0: .data..read_mostly+0xe260: data relocation to !ENDBR: dcbnl_netdevice_event+0x0

Fixes: 89bc853e ("objtool: Find unused ENDBR instructions")
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/762e88d51300e8eaf0f933a5b0feae20ac033bea.1650300597.git.jpoimboe@redhat.com

tools/objtool/check.c

@@ -3817,11 +3817,8 @@ static int validate_ibt(struct objtool_file *file)
 			struct instruction *dest;
 
 			dest = validate_ibt_reloc(file, reloc);
-			if (is_data && dest && !dest->noendbr) {
-				warn_noendbr("data ", reloc->sym->sec,
-					     reloc->sym->offset + reloc->addend,
-					     dest);
-			}
+			if (is_data && dest && !dest->noendbr)
+				warn_noendbr("data ", sec, reloc->offset, dest);
 		}
 	}