Revert previous commit. As ru explains:

In the old world (as the surrounding comment in makefile says), there
 was the /usr/libexec/ld-elf.so.1 binary which is now a symlink to
 /libexec/ld-elf.so.1. To symlink, we need to make sure that the
 _target_ (and the target is /usr/libexec/ld-elf.so.1) doesn't have
 "schg" flag set. A real solution is to protect the chflags call only if
 target exists, like we do in usr.bin/tip/tip/Makefile.

Requested by:	ru

libexec/rtld-elf/Makefile

@@ -48,7 +48,7 @@ dyn_hack.so:
 # Since moving rtld-elf to /libexec, we need to create a symlink.
 # Fixup the existing binary that's there so we can symlink over it.
 beforeinstall:
-	-chflags noschg ${DESTDIR}/${BINDIR}/${PROG}
+	-chflags noschg ${DESTDIR}/usr/libexec/${PROG}
 
 .PATH: ${.CURDIR}/${MACHINE_ARCH}