Use size_t for blob lengths in utilfdt_read*

It's more appropriate than off_t since it is, after all, a size not an
offset.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>

fdtdump.c

@@ -181,7 +181,7 @@ int main(int argc, char *argv[])
 	char *buf;
 	bool debug = false;
 	bool scan = false;
-	off_t len;
+	size_t len;
 
 	fprintf(stderr, "\n"
 "**** fdtdump is a low-level debugging tool, not meant for general use.\n"

fdtoverlay.c

@@ -60,7 +60,7 @@ static int do_fdtoverlay(const char *input_filename,
 {
 	char *blob = NULL;
 	char **ovblob = NULL;
-	off_t blob_len, ov_len, total_len;
+	size_t blob_len, ov_len, total_len;
 	int i, ret = -1;
 
 	blob = utilfdt_read(input_filename, &blob_len);

util.c

@@ -227,11 +227,11 @@ char get_escape_char(const char *s, int *i)
 	return val;
 }
 
-int utilfdt_read_err(const char *filename, char **buffp, off_t *len)
+int utilfdt_read_err(const char *filename, char **buffp, size_t *len)
 {
 	int fd = 0;	/* assume stdin */
 	char *buf = NULL;
-	off_t bufsize = 1024, offset = 0;
+	size_t bufsize = 1024, offset = 0;
 	int ret = 0;
 
 	*buffp = NULL;
@@ -269,7 +269,7 @@ int utilfdt_read_err(const char *filename, char **buffp, off_t *len)
 	return ret;
 }
 
-char *utilfdt_read(const char *filename, off_t *len)
+char *utilfdt_read(const char *filename, size_t *len)
 {
 	char *buff;
 	int ret = utilfdt_read_err(filename, &buff, len);

util.h

@@ -101,7 +101,7 @@ char get_escape_char(const char *s, int *i);
  * @param len		If non-NULL, the amount of data we managed to read
  * @return Pointer to allocated buffer containing fdt, or NULL on error
  */
-char *utilfdt_read(const char *filename, off_t *len);
+char *utilfdt_read(const char *filename, size_t *len);
 
 /**
  * Read a device tree file into a buffer. Does not report errors, but only
@@ -113,7 +113,7 @@ char *utilfdt_read(const char *filename, off_t *len);
  * @param len		If non-NULL, the amount of data we managed to read
  * @return 0 if ok, else an errno value representing the error
  */
-int utilfdt_read_err(const char *filename, char **buffp, off_t *len);
+int utilfdt_read_err(const char *filename, char **buffp, size_t *len);
 
 /**
  * Write a device tree buffer to a file. This will report any errors on