drivers: bluetooth: rpmsg: validate heap size configuration

Added a build-time assert to check if heap memory configuration to
make sure that it can accomodate RPMsg queue allocations.

Ref: NCSDK-5479

Signed-off-by: Kamil Piszczek <Kamil.Piszczek@nordicsemi.no>

drivers/bluetooth/hci/rpmsg_nrf53.c

@@ -48,6 +48,9 @@ BUILD_ASSERT((SHM_START_ADDR + SHM_SIZE - SHM_BASE_ADDRESS)
 
 #define VDEV_STATUS_ADDR    SHM_BASE_ADDRESS
 
+BUILD_ASSERT(CONFIG_HEAP_MEM_POOL_SIZE >= 1024,
+	"Not enough heap memory for RPMsg queue allocation");
+
 /* End of configuration defines */
 
 static metal_phys_addr_t shm_physmap[] = { SHM_START_ADDR };