Add notes about known bugs in lis and xosd driver and timing.h.

BUGS

@@ -7,6 +7,8 @@ V0.5dev:
     a non full block from the vBar.
   - On Solaris the mtc_s16209x driver fails to compile. Configure LCDproc to
     exclude this driver.
+  - On FreeBSD drivers using the pthread library are known not to work.
+    Currently affected are the lis and xosd driver.
 
 
 Bugs in previous versions (not checked if the still exist):

server/drivers/timing.h

@@ -164,6 +164,7 @@ static inline void timing_uPause (int usecs) {
 	}
 #else // using I/O timing
       // Assuming every port I/O takes 1us
+      // FIXME: Does this work at all? Where does 'port' come from?
 	for (int i=0; i < usecs; ++i)
 		port_in(port);
 #endif