build: Revert "Use -lresolv in LIBS with rust on OSX."

This reverts commit 2ac9734bd21f3eecb20560cde5c4037230029157.

 * FIXES #25341: https://bugs.torproject.org/25341

Signed-off-by: Isis Lovecruft <isis@torproject.org>

Makefile.am

@@ -26,8 +26,7 @@ TESTING_TOR_BINARY=$(top_builddir)/src/or/tor$(EXEEXT)
 endif
 
 if USE_RUST
-rust_ldadd=$(top_builddir)/src/rust/target/release/@TOR_RUST_STATIC_NAME@ \
-	@TOR_RUST_EXTRA_LIBS@
+rust_ldadd=$(top_builddir)/src/rust/target/release/@TOR_RUST_UTIL_STATIC_NAME@
 else
 rust_ldadd=
 endif

configure.ac

@@ -468,15 +468,6 @@ if test "x$enable_rust" = "xyes"; then
     fi
   fi
 
-  dnl This is a workaround for #46797
-  dnl (a.k.a https://github.com/rust-lang/rust/issues/46797 ).  Once the
-  dnl upstream bug is fixed, we can remove this workaround.
-  case "$host_os" in
-      darwin*)
-        TOR_RUST_EXTRA_LIBS="-lresolv"
-	;;
-  esac
-
   dnl For now both MSVC and MinGW rust libraries will output static libs with
   dnl the MSVC naming convention.
   if test "$bwin32" = "true"; then
@@ -503,8 +494,6 @@ if test "x$enable_rust" = "xyes"; then
   AC_MSG_RESULT([$RUSTC_VERSION])
 fi
 
-AC_SUBST(TOR_RUST_EXTRA_LIBS)
-
 AC_SEARCH_LIBS(socket, [socket network])
 AC_SEARCH_LIBS(gethostbyname, [nsl])
 AC_SEARCH_LIBS(dlopen, [dl])