Hi,
I never used or are familiar with the book you are using (I'm seeing this site for the first time), but it seems you have made a mistake, probably when building the
Xorg Protocol Headers headers and/or the
pkg-config-0.22 step.
Why did you decide to use the BLFS 6.3 book from theskycenter and not the official one:
BLFS 6.3?
Anyway, hope this helps.