os: minor fixes

vlib/os/os_nix.c.v

@@ -137,21 +137,6 @@ pub fn get_error_msg(code int) string {
 	return posix_get_error_msg(code)
 }
 
-// convert any value to []byte (LittleEndian) and write it
-// for example if we have write(7, 4), "07 00 00 00" gets written
-// write(0x1234, 2) => "34 12"
-pub fn (mut f File) write_bytes(data voidptr, size int) {
-/*
-	$if linux {
-		$if !android {
-			C.syscall(sys_write, f.fd, data, 1)
-			return
-		}
-	}
-*/
-	C.fwrite(data, 1, size, f.cfile)
-}
-
 pub fn (mut f File) close() {
 	if !f.opened {
 		return