.note.sgxmeta invalid ELF section

This toolchain produces ELF files with an invalid section. Here is the beginning of a typical .note.sgxmeta section created by the toolchain:

```
Contents of section .note.sgxmeta:
0000 0d000000 00100000 01000000 7367785f ............sgx_
0010 6d657461 64617461 004c0e5d 639402a8 metadata.L.]c...
```

Note that the "desc" data starts immediately after the "name" field at offset 0x19, but the ELF format specifies that "name" be padded so that "desc" is 4-byte aligned https://docs.oracle.com/cd/E23824_01/html/819-0690/chapter6-18048.html.