Waite for Action SIDE Cargo Door

Hi,

on PMDG_747_Introduction.pdf Page 60 Is this to read:

When using a cargo variant, the nose and side cargo doors
require that a power source be available, but not in use. As an
example, if you are using APU power, GEN1 can be used for
power, but GEN2 will need to be switched off (left AVAIL) in order
for the doors to operate.

Maybe dis can be noticed in lib-GSX.lua to prevent unnecessary error messages