Some user space applications like lsof include both headers for
pause(3) and pause(9). That means we now have two conflicting
definitions. While previously (unitl 7ea1cac248574ed06) being a macro
this was dealt with but already caused trouble. To avoid constant
workarounds provide a way to only "hide" pause(9).
For the moment that is the lsof header guard but like NO_SYSCTL_DESCR,
NO_OBSOLETE_CODE, and some other NO_ guards, we could name this
NO_KERNEL_PAUSE and define that in lsof allowing us to remove some
other attempted workarounds in the future.
X-MFC with: 7ea1cac248574ed06c7823ffbfb9a60157240e57