treewide: replace with error() with pr_err()

U-Boot widely uses error() as a bit noisier variant of printf().

This macro causes name conflict with the following line in
include/linux/compiler-gcc.h:

  # define __compiletime_error(message) __attribute__((error(message)))

This prevents us from using __compiletime_error(), and makes it
difficult to fully sync BUILD_BUG macros with Linux.  (Notice
Linux's BUILD_BUG_ON_MSG is implemented by using compiletime_assert().)

Let's convert error() into now treewide-available pr_err().

Done with the help of Coccinelle, excluing tools/ directory.

The semantic patch I used is as follows:

// <smpl>
@@@@
-error
+pr_err
 (...)
// </smpl>

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
[trini: Re-run Coccinelle]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/dfu/dfu_tftp.c b/drivers/dfu/dfu_tftp.c
index cd71708..62bf797 100644
--- a/drivers/dfu/dfu_tftp.c
+++ b/drivers/dfu/dfu_tftp.c
@@ -43,7 +43,7 @@
 	alt_setting_num = dfu_get_alt(sb);
 	free(sb);
 	if (alt_setting_num < 0) {
-		error("Alt setting [%d] to write not found!",
+		pr_err("Alt setting [%d] to write not found!",
 		      alt_setting_num);
 		ret = -ENODEV;
 		goto done;
@@ -51,7 +51,7 @@
 
 	dfu = dfu_get_entity(alt_setting_num);
 	if (!dfu) {
-		error("DFU entity for alt: %d not found!", alt_setting_num);
+		pr_err("DFU entity for alt: %d not found!", alt_setting_num);
 		ret = -ENODEV;
 		goto done;
 	}