FTP: Update RequestHeader struct and Opcode enum
FTP: Remove CRC32.
FTP: remove reserved uint32 from header.
FTP: Update unit-test, remove crc32 test case.
FTP: remove padding zeroing.
Merge pull request #865 from vooon/ftp_opcode

FTP request opcode
Fix bug with new kErrFailErrno code
Merge pull request #868 from DonLakeFlyer/FTPFix

Fix bug with new kErrFailErrno code