ASoC: SOF: amd: Add branch prediction hint in ACP IRQ handler

The conditional involving sdev->first_boot in acp_sof_ipc_irq_thread()
will succeed only once, i.e. during the very first run of the
DSP firmware.

Use the unlikely() annotation to help improve branch prediction
accuracy.

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Reviewed-by: Venkata Prasad Potturu <venkataprasad.potturu@amd.com>
Link: https://patch.msgid.link/20250207-sof-vangogh-fixes-v1-4-67824c1e4c9a@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: cristicc

sound/soc/sof/amd/acp-ipc.c

@@ -165,7 +165,7 @@ irqreturn_t acp_sof_ipc_irq_thread(int irq, void *context)
 	int dsp_msg, dsp_ack;
 	unsigned int status;
 
-	if (sdev->first_boot && sdev->fw_state != SOF_FW_BOOT_COMPLETE) {
+	if (unlikely(sdev->first_boot && sdev->fw_state != SOF_FW_BOOT_COMPLETE)) {
 		acp_mailbox_read(sdev, sdev->dsp_box.offset, &status, sizeof(status));
 
 		if ((status & SOF_IPC_PANIC_MAGIC_MASK) == SOF_IPC_PANIC_MAGIC) {