Compilers like GCC require comments on lines like `#endif rdmsr`. Since
the rdmsr macro was only being used in arch_prctl(), I've localized the
macro, and I'm considering deleting arch_prctl() too, since there isn't
any way to have mem segments unfortunately across operating systems ;_;
The remaining changed lines are due to clang-format which runs on auto.
blinkenlights now does a pretty good job emulating what happens when
binaries boot from BIOS into long mode. So it's been much easier to
debug the bare metal process and wrinkle out many issues.
