test/README: fix advice for testsuite debugging

KERNEL_APPEND="systemd.unit=multi-user.target" is not very useful, because the
machine will still shut down as soon as the tests succeeds or fails. But
INTERACTIVE_DEBUG=1 works great, so let's simplify the instructions and
recommend that.

diff --git a/test/README.testsuite b/test/README.testsuite
index 9070d0c60c9caba2d0d6abe1d2ab33ddf8cbc165..695cce15aabb64bd2f0fa5703a59070dfbeca1d0 100644 (file)
--- a/test/README.testsuite
+++ b/test/README.testsuite
@@ -99,7 +99,7 @@ INTERACTIVE_DEBUG=1
     the test, etc.)
 
 The kernel and initrd can be specified with $KERNEL_BIN and $INITRD. (Fedora's
-or Debian's default kernel path and initrd are used by default)
+or Debian's default kernel path and initrd are used by default.)
 
 A script will try to find your qemu binary. If you want to specify a different
 one with $QEMU_BIN.
@@ -107,12 +107,12 @@ one with $QEMU_BIN.
 Debugging the qemu image
 ========================
 
-If you want to log in the testsuite virtual machine, you can specify additional
-kernel command line parameter with $KERNEL_APPEND and then log in as root.
+If you want to log in the testsuite virtual machine, use INTERACTIVE_DEBUG=1
+and log in as root:
 
-$ sudo make -C test/TEST-01-BASIC KERNEL_APPEND="systemd.unit=multi-user.target" run
+$ sudo make -C test/TEST-01-BASIC INTERACTIVE_DEBUG=1 run
 
-Root password is empty.
+The root password is empty.
 
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