libite: Improve error handling for copyfile() and rsync()

When using the simple rsync() or copyfile() functions of libite some
error codes should not be interpreted as error.  I.e., if a file or
directory already exists when attempting to create it.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

copyfile.c

@@ -179,6 +179,7 @@ int copy_filep(FILE *src, FILE *dst)
 		return errno;
 
 	while (1) {
+      errno = 0;
 		if (!fgets(buf, BUFSIZ, src)) {
 			if (errno == EINTR) {
 				clearerr(src);