boot-test: enable by default in debug builds

Now that the DSP panic has been fixed, re-enable boot-testing in
debug builds. Note, that we need to increase ztest thread stack size
for the VMH test.

Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>

Author: lyakh

app/debug_overlay.conf

@@ -1,9 +1,9 @@
 CONFIG_DEBUG=y
 CONFIG_ASSERT=y
 
-# Disabled until DSP panic #8621 is fixed
-# CONFIG_ZTEST=y
-# CONFIG_SOF_BOOT_TEST=y
+CONFIG_ZTEST=y
+CONFIG_TEST_EXTRA_STACK_SIZE=7168
+CONFIG_SOF_BOOT_TEST=y
 
 CONFIG_DAI_VERBOSE_GLITCH_WARNINGS=y