[nrf fromlist] ipc: icmsg: increase stack size of RX work queue thread

Increases default size of stack used by work queue RX thread
from 1024 to 1280 to avoid memory issues.

After adding the buffer with the default size of 128
that is allocated on the thread's stack (see #77552),
there is too little stack left during heavy stress.

Upstream PR: zephyrproject-rtos/zephyr#79557

Signed-off-by: Piotr Koziar <[email protected]>

Author: piotrkoziar

subsys/ipc/ipc_service/lib/Kconfig.icmsg

@@ -51,7 +51,7 @@ if IPC_SERVICE_BACKEND_ICMSG_WQ_ENABLE
 
 config IPC_SERVICE_BACKEND_ICMSG_WQ_STACK_SIZE
 	int "Size of RX work queue stack"
-	default 1024
+	default 1280
 	help
 	  Size of stack used by work queue RX thread. This work queue is
 	  created to prevent notifying service users about received data