drivers/firmware/broadcom/bcm47xx_nvram.c: use __ioread32_copy() instead of open-coding

Now that we have a generic library function for this, replace the
open-coded instance.

Signed-off-by: Stephen Boyd <[e-mail]>
Cc: Hauke Mehrtens <[e-mail]>
Cc: <[e-mail]>
Cc: Paul Walmsley <[e-mail]>
Cc: Bjorn Andersson <[e-mail]>
Cc: David Howells <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/firmware/broadcom/bcm47xx_nvram.c

···
 static int nvram_find_and_copy(void __iomem *iobase, u32 lim)
 {
 	struct nvram_header __iomem *header;
-	int i;
 	u32 off;
-	u32 *src, *dst;
 	u32 size;
 
 	if (nvram_len) {
···
 	return -ENXIO;
 
 found:
-	src = (u32 *)header;
-	dst = (u32 *)nvram_buf;
-	for (i = 0; i < sizeof(struct nvram_header); i += 4)
-		*dst++ = __raw_readl(src++);
+	__ioread32_copy(nvram_buf, header, sizeof(*header) / 4);
 	header = (struct nvram_header *)nvram_buf;
 	nvram_len = header->len;
 	if (nvram_len > size) {
···
 		nvram_len = NVRAM_SPACE - 1;
 	}
 	/* proceed reading data after header */
-	for (; i < nvram_len; i += 4)
-		*dst++ = readl(src++);
+	__ioread32_copy(nvram_buf + sizeof(*header), header + 1,
+			DIV_ROUND_UP(nvram_len, 4));
 	nvram_buf[NVRAM_SPACE - 1] = '\0';
 
 	return 0;