Some #include statements were not properly protected. This will go unnoted
on most systems as openssl/comp.h tends to be installed as a system header
file by default but may become visible when cross compiling.

shell ones.

test). (Coverity ID 148).

test for them!

(Coverity ID 135).

(Coverity ID 140).

PR: 1803

unsigned long must be attributed to 16-bit support. As we don't support
16-bit platoforms anymore, there is no reason to waste twice required
space on CAST S-boxes (16KB vs. 8KB) or key schedule.