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/usb/gadget/at91_udc.c b/drivers/usb/gadget/at91_udc.c
index 9df6d32..ad2f606 100644
--- a/drivers/usb/gadget/at91_udc.c
+++ b/drivers/usb/gadget/at91_udc.c
@@ -1456,7 +1456,7 @@
 
 	ret = driver->bind(&udc->gadget);
 	if (ret) {
-		error("driver->bind() returned %d\n", ret);
+		pr_err("driver->bind() returned %d\n", ret);
 		udc->driver = NULL;
 	}
 
@@ -1468,7 +1468,7 @@
 	struct at91_udc *udc = controller;
 
 	if (!driver || !driver->unbind || !driver->disconnect) {
-		error("bad paramter\n");
+		pr_err("bad paramter\n");
 		return -EINVAL;
 	}