dist-x86_64-linux: for gcc add --disable-multilib, as there no need to build 32-bit. Remove linked 32-bit libraries, dist-i686-linux have it's own build-gcc.sh

Author: klensy

src/ci/docker/host-x86_64/dist-x86_64-linux/build-gcc.sh

@@ -30,16 +30,12 @@ cd ../gcc-build
 hide_output ../gcc-$GCC/configure \
     --prefix=/rustroot \
     --enable-languages=c,c++ \
-    --disable-gnu-unique-object
+    --disable-gnu-unique-object \
+    --disable-multilib
 hide_output make -j$(nproc)
 hide_output make install
 ln -s gcc /rustroot/bin/cc
 
 cd ..
 rm -rf gcc-build
 rm -rf gcc-$GCC
-
-# FIXME: clang doesn't find 32-bit libraries in /rustroot/lib,
-# but it does look all the way under /rustroot/lib/[...]/32,
-# so we can link stuff there to help it out.
-ln /rustroot/lib/*.{a,so} -rst /rustroot/lib/gcc/x86_64-pc-linux-gnu/$GCC/32/