style(expect): normalize debugging messages

A minor style cleanup to the messages printed by the Expect scripts to
make them a bit more consistent and descriptive.

Signed-off-by: Chris Kay <chris.kay@arm.com>
Change-Id: Ibd8ccb4423bd5aaeffc99c2f3602123794dc6200
(cherry picked from commit 78ea2c38582da41eb8f9509a2130e702cdf0f1c9)
diff --git a/expect/timeout.inc b/expect/timeout.inc
index 7e07ff6..6d5d0de 100644
--- a/expect/timeout.inc
+++ b/expect/timeout.inc
@@ -4,32 +4,32 @@
 # SPDX-License-Identifier: BSD-3-Clause
 #
 
-puts "<<test completed, waiting for EOF or timeout>>"
+message "test completed, waiting for EOF or timeout"
 
 expect {
     "Exiting tests." {
-        puts "<<expected hang, found TFTF completion>>"
+        message "expected hang, found TFTF completion"
     }
 
     "PANIC in EL3." {
-        puts "<<expected hang, found crash dump>>"
+        message "expected hang, found crash dump"
     }
 
     "Unhandled Exception in EL3." {
-        puts "<<expected hang, found crash dump>>"
+        message "expected hang, found crash dump"
     }
 
     "Unhandled Exception from EL" {
-        puts "<<expected hang, found crash dump>>"
+        message "expected hang, found crash dump"
     }
 
     eof {
-        puts "<<stream closed as expected, exiting>>"
+        message "stream closed as expected, exiting"
         exit 0
     }
 
     timeout {
-        puts "<<timeout triggered as expected, exiting>>"
+        message "timeout triggered as expected, exiting"
         exit_uart 0
     }
 }