ptl: userspace: temporarily switch to stack pool

This fixes sporadic CI endurance test failures. Once Zephyr merges
"kernel: dynamic stack to cached area if coherence" we should be able
to switch back to dynamic stack allocation.

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

Author: lyakh

app/boards/intel_adsp_ace30_ptl.conf

@@ -70,8 +70,11 @@ CONFIG_WINSTREAM_CONSOLE=n
 # Userspace options
 CONFIG_USERSPACE=y
 CONFIG_DYNAMIC_THREAD=y
-CONFIG_DYNAMIC_THREAD_ALLOC=y
-CONFIG_DYNAMIC_THREAD_PREFER_ALLOC=y
-CONFIG_SOF_STACK_SIZE=8192
+CONFIG_DYNAMIC_THREAD_ALLOC=n
+CONFIG_DYNAMIC_THREAD_PREFER_ALLOC=n
+CONFIG_DYNAMIC_THREAD_PREFER_POOL=y
+CONFIG_DYNAMIC_THREAD_POOL_SIZE=4
+CONFIG_DYNAMIC_THREAD_STACK_SIZE=4096
+CONFIG_SOF_STACK_SIZE=4096
 CONFIG_SOF_USERSPACE_PROXY=y
 CONFIG_MAX_THREAD_BYTES=3