Fix std::fs::File::metadata permission on WASI target

Previously `std::fs::File::metadata` on wasm32-wasi would call `fd_filestat_get`
to get metadata associated with fd, but that fd is opened without
RIGHTS_FD_FILESTAT_GET right, so it will failed on correctly implemented WASI
environment.

This change instead to add the missing rights when opening an fd.

Author: ibmibmibm

library/std/src/sys/wasi/fs.rs

@@ -331,6 +331,7 @@ impl OpenOptions {
         // FIXME: some of these should probably be read-only or write-only...
         base |= wasi::RIGHTS_FD_ADVISE;
         base |= wasi::RIGHTS_FD_FDSTAT_SET_FLAGS;
+        base |= wasi::RIGHTS_FD_FILESTAT_GET;
         base |= wasi::RIGHTS_FD_FILESTAT_SET_TIMES;
         base |= wasi::RIGHTS_FD_SEEK;
         base |= wasi::RIGHTS_FD_SYNC;