According to style(9):
> normally, include <sys/types.h> OR <sys/param.h>, but not both.
(<sys/param.h> already includes <sys/types.h> when LOCORE is not defined).
As part of the code refactoring to support FORTIFY_SOURCE we want
a new subdirectory "secure" to keep the files related to security.
Move the stack protector functions to this new directory.
No functional change.
Differential Review: https://reviews.freebsd.org/D3333