drivers: i2s: i2s_ll_stm32: tx_stream_disable: Add busy wait

Add a k_busy_wait to the function tx_stream_disable
to be able to complete the drain of the TX queue before disabling.

Signed-off-by: IBEN EL HADJ MESSAOUD Marwa <marwa.ibenelhadjmessaoud-ext@st.com>

drivers/i2s/i2s_ll_stm32.c

@@ -931,6 +931,8 @@ static void tx_stream_disable(struct stream *stream, const struct device *dev)
 		stream->mem_block = NULL;
 	}
 
+	/* Wait for TX queue to drain before disabling */
+	k_busy_wait(100);
 	LL_I2S_Disable(cfg->i2s);
 
 	active_dma_tx_channel[stream->dma_channel] = NULL;