Put ifdefs around Linux-specific header/function.

Closes #2366.
(cherry picked from commit 2d4d2d807d98fd9cd3b49891faf0b34976330915)

lib/exceptionhandler/exceptionhandler.c

@@ -122,10 +122,12 @@ static LONG WINAPI windowsExceptionHandler(PEXCEPTION_POINTERS pExceptionInfo)
 # include <sys/stat.h>
 # include <sys/wait.h>
 # include <sys/utsname.h>
+#ifdef WZ_OS_LINUX
 # include <sys/prctl.h>
 #ifndef PR_SET_PTRACER
 # define PR_SET_PTRACER 0x59616d61  // prctl will ignore unknown options
 #endif
+#endif
 
 // GNU extension for backtrace():
 # if defined(__GLIBC__)
@@ -434,8 +436,10 @@ static pid_t execGdb(int const dumpFile, int* gdbWritePipe)
 	// Check to see if we're the parent
 	if (pid != 0)
 	{
+#ifdef WZ_OS_LINUX
 		// Allow tracing the process, some hardened kernel configurations disallow this.
 		prctl(PR_SET_PTRACER, pid, 0, 0, 0);
+#endif
 
 		// Return the write end of the pipe
 		*gdbWritePipe = gdbPipe[1];