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/env/sf.c b/env/sf.c
index 6f74371..e51b1ae 100644
--- a/env/sf.c
+++ b/env/sf.c
@@ -236,7 +236,7 @@
 
 	ret = env_import((char *)ep, 0);
 	if (!ret) {
-		error("Cannot import environment: errno = %d\n", errno);
+		pr_err("Cannot import environment: errno = %d\n", errno);
 		set_default_env("!env_import failed");
 	}