Remove AES stuff from uart.c if no ENABLE_PWRON_PASSWORD, save ~384 bytes

[prokrypt]

I'm not totally sure how AES is used, but nothing exploded...
prokrypt@8dd94f8

[armel]

Hummm playing with UART commands is dangerous.
I agree with you, deleting what you suggest doesn't seem to create a problem.
But I'm still a little worried.
Frankly, I don't know what to make of it.