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>

cmd/regulator.c

@@ -71,7 +71,7 @@ static int curr_dev_and_platdata(struct udevice **devp,
 
 	*uc_pdata = dev_get_uclass_platdata(*devp);
 	if (!*uc_pdata) {
-		error("Regulator: %s - missing platform data!", currdev->name);
+		pr_err("Regulator: %s - missing platform data!", currdev->name);
 		return CMD_RET_FAILURE;
 	}