ath10k: fix NAPI enable/disable symmetry for AHB interface

Move NAPI enable to 'ath10k_ahb_hif_start' from
'ath10k_ahb_hif_power_up'. This is to maintain the symmetry
of calling napi_enable() from ath10k_ahb_hif_start() so that it
matches with  napi_disable() being called from ath10k_pci_hif_stop().

This change is based on the crash fix from Kalle for PCI interface in
commit 1427228d ("ath10k: fix napi crash during rmmod when probe
firmware fails").
Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qti.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath10k/ahb.c

@@ -640,6 +640,7 @@ static int ath10k_ahb_hif_start(struct ath10k *ar)
 {
 	ath10k_dbg(ar, ATH10K_DBG_BOOT, "boot ahb hif start\n");
 
+	napi_enable(&ar->napi);
 	ath10k_ce_enable_interrupts(ar);
 	ath10k_pci_enable_legacy_irq(ar);
 
@@ -692,7 +693,6 @@ static int ath10k_ahb_hif_power_up(struct ath10k *ar)
 		ath10k_err(ar, "could not wake up target CPU: %d\n", ret);
 		goto err_ce_deinit;
 	}
-	napi_enable(&ar->napi);
 
 	return 0;