nvme: fix for big endian systems

writel() and co. already include the endian swap;  doing the swap twice
is, er, unhelpful.

Tested on a P4080DS, which boots perfectly fine off NVMe with this.

Signed-off-by: David Lamparter <equinox@diac24.net>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/nvme/nvme.c b/drivers/nvme/nvme.c
index c61dab2..d554ec5 100644
--- a/drivers/nvme/nvme.c
+++ b/drivers/nvme/nvme.c
@@ -157,7 +157,7 @@
 
 	invalidate_dcache_range(start, stop);
 
-	return le16_to_cpu(readw(&(nvmeq->cqes[index].status)));
+	return readw(&(nvmeq->cqes[index].status));
 }
 
 /**
@@ -221,7 +221,7 @@
 	}
 
 	if (result)
-		*result = le32_to_cpu(readl(&(nvmeq->cqes[head].result)));
+		*result = readl(&(nvmeq->cqes[head].result));
 
 	if (++head == nvmeq->q_depth) {
 		head = 0;
@@ -304,7 +304,7 @@
 {
 	dev->ctrl_config &= ~NVME_CC_SHN_MASK;
 	dev->ctrl_config |= NVME_CC_ENABLE;
-	writel(cpu_to_le32(dev->ctrl_config), &dev->bar->cc);
+	writel(dev->ctrl_config, &dev->bar->cc);
 
 	return nvme_wait_ready(dev, true);
 }
@@ -313,7 +313,7 @@
 {
 	dev->ctrl_config &= ~NVME_CC_SHN_MASK;
 	dev->ctrl_config &= ~NVME_CC_ENABLE;
-	writel(cpu_to_le32(dev->ctrl_config), &dev->bar->cc);
+	writel(dev->ctrl_config, &dev->bar->cc);
 
 	return nvme_wait_ready(dev, false);
 }