lava-expect: migrate expect into lava-expect scripts

Parent commit enables Lava Interactive Actions into FVP LAVA jobs and
this commit feeds with 'lava expect' strings targeting mainly 'UART0
scripts'.

This work is done in a separate folder, `lava-expect`,
instead of expect with a reason: both expect strings should be
developed in parallel, where the expect strings are either used by
Legacy CI or local development and `lava-expect` strings are intended
for Open CI LAVA testing.

Note that this patch does not migrate all current expect strings, several
are pending as indicated in the list below. Coming patches would cover
these:

* hold_uart.exp
* linux-tpm.exp
* spm-edk2-uart0.exp
* spm-edk2-uart2.exp
* spm-linux-uart0.exp
* spm-optee-sp-uart1.exp
* spm-uart2.exp
* timeout.exp
* timeout_spmin_roxlattables.exp
* timeout_test.exp
* tpm-logs.exp

Signed-off-by: Leonardo Sandoval <leonardo.sandoval@linaro.org>
Change-Id: I386be3fb1a73c491f01a27fb05a4215f0e789f26
diff --git a/lava-expect/linux.inc b/lava-expect/linux.inc
new file mode 100644
index 0000000..8430f2b
--- /dev/null
+++ b/lava-expect/linux.inc
@@ -0,0 +1,16 @@
+#
+# Copyright (c) 2021 Arm Limited. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+# Script to interact with a Linux kernel
+#
+
+# Expect 8 CPUs in total by default
+if [ -z "${num_cpus}" ]; then
+	num_cpus=8
+fi
+
+expect_string+=('Linux version')
+expect_string+=("SMP: Total of ${num_cpus} processors activated")
+expect_string+=('Freeing unused kernel memory')