testimage: Run commands in target and host when test fails

This patch modify three files altought two of them
are minimal modifications. This version includes
the changes proposed by Paul.

testimage.bbclass:
    Create new vars for easy modification of the dump
directory and commands to be run on host and target
when a test fails
    TESTIMAGE_DUMP_DIR: Directory to save the dumps
    testimage_dump_target: Commands to run on target
    testimage_dump_host: Commands to run on host

oetest.py:
    - Allow to use the vars defined in testimage class
    - Now able to run commands in the host and dump the
      results
    - Fix an issue with the condition where to run the
      dump commands (Before it run the commands every
      test after a failure, now it runs the commands only
      in tests that failed)
    - Fix the output to stdout

[YOCTO #8118]

(From OE-Core rev: 26fe645457633f90bb5ddbb12f5f7b9ca4a06cc5)

(From OE-Core rev: 7b4fbbf979ed22434b8e3f83ae145139bb0d9fc7)

Signed-off-by: Mariano Lopez <mariano.lopez@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/testimage.bbclass

@@ -56,6 +56,30 @@ TESTIMAGEDEPENDS_qemuall = "qemu-native:do_populate_sysroot qemu-helper-native:d
 TESTIMAGELOCK = "${TMPDIR}/testimage.lock"
 TESTIMAGELOCK_qemuall = ""
 
+TESTIMAGE_DUMP_DIR ?= "/tmp/oe-saved-tests/"
+
+testimage_dump_target () {
+    top -bn1
+    ps
+    free
+    df
+    _ping
+    dmesg
+    netstat -an
+    ip address
+    _logs
+}
+
+testimage_dump_host () {
+    top -bn1
+    ps -ef
+    free
+    df
+    memstat
+    dmesg
+    netstat -an
+}
+
 python do_testimage() {
     testimage_main(d)
 }