Install 32-bit libc++

Author: alexcrichton

ci/azure-steps.yml

@@ -5,7 +5,7 @@ steps:
 
   - bash: sudo apt-get install gcc-multilib
     condition: eq( variables['Agent.OS'], 'Linux' )
-    displayName: Install gcc-multilib
+    displayName: Install g++-multilib
 
   - script: cargo build
     displayName: "Normal build"