Revert "libc: Implement bsort(3) a bitonic type of sorting algorithm."

Some points for the future:

• libc is not the right place for sorting algorithms. Probably libutil is better suited for this purpose or a dedicated libsort. Should move all sorting algorithms away from libc eventually.
• CheriBSD uses capabilities for memory access, and could benefit from a standard memswap() function.
• Do something about qsort() in FreeBSD's libc like:
  • Mark it deprecated on FreeBSD, as a first step, due to missing limits on CPU time.
  • Audit the use of qsort() in the FreeBSD base system and consider swapping to other existing sorting algorithms.

Discussed with: brooks@

Differential Revision: https://reviews.freebsd.org/D36493

This reverts commit a7469c9c0a504a5e6e9b89e148cd78df5e67ff7f.
This reverts commit 7d65a450cdcc7cc743f2ecd114ba3428a21c0033.
This reverts commit 8dcf3a82c54cb216df3213a013047907636a01da.