Support for decrypting PS1 ELFs

Hello! Requesting to add decryption support for PS1 (loader) ELFs in the EBOOT.PBP of PS1 / PSone titles.

I get the following error when using pspdecrypt 1.0:

`Decryption failed for tag DAA06F0`

In testing, i used the Tekken 2 and Resident Evil 1: Directors Cut ELF to try to decrypt. I can upload the ELF if need be for testing :P