trace-kernel-build: Disable pipefail as it causes build to exit

Change-Id: I8e9f8f8d2fb67c6c8a57892f0f630c32878e2d77
Signed-off-by: Joel Stanley <joel@jms.id.au>
diff --git a/trace-kernel-build.sh b/trace-kernel-build.sh
index 2f5d95f..7f72dec 100755
--- a/trace-kernel-build.sh
+++ b/trace-kernel-build.sh
@@ -65,8 +65,7 @@
 cat > "${WORKSPACE}"/build.sh << EOF_SCRIPT
 #!/bin/bash
 
-set -x
-set -e -o pipefail
+set -xe
 
 cd ${WORKSPACE}