refactor(expect): factor common Expect failure cases into `handle-arguments.inc`

This change factors common Expect failure cases like timeouts and
premature EOFs into the common `handle-arguments.inc` Expect script
fragment.

This fragment now implicitly inserts a timeout handler and an EOF
handler into every expectation introduced after the inclusion of this
fragment. These handlers have the lowest priority, so can be overridden
if necessary.

Signed-off-by: Chris Kay <chris.kay@arm.com>
Change-Id: Ia92f0046ea123d3ed213aa76dc5fce6163471451
diff --git a/expect/spm-uart2.exp b/expect/spm-uart2.exp
index fa05f0c..f9b22eb 100644
--- a/expect/spm-uart2.exp
+++ b/expect/spm-uart2.exp
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2020, Arm Limited. All rights reserved.
+# Copyright (c) 2020-2022, Arm Limited. All rights reserved.
 #
 # SPDX-License-Identifier: BSD-3-Clause
 #
@@ -10,9 +10,6 @@
 	"Booting Secure Partition"  {
 		puts "<<SP entry>>"
 	}
-	timeout {
-		exit_uart -1
-	}
 }
 
 # UART2 captures prints from SP0. If we exit from here, expect script will stop