Enable "set -euo pipefail" in all bash scripts.

This enables "set -e", "set -u", and "set -o pipefail", which
catch common errors.

cranelift/format-all.sh

@@ -1,10 +1,8 @@
 #!/bin/bash
+set -euo pipefail
 
 # Format all sources using rustfmt.
 
-# Exit immediately on errors.
-set -e
-
 cd $(dirname "$0")
 
 # Make sure we can find rustfmt.