Mention CONFIG_HIGH_RES_TIMERS kernel setting.

README

 mptsd do not depend on any external libraries. There are two source code
 dependancies that come with mptsd - libfuncs and libtsfuncs.
 
+Make sure your kernel has CONFIG_HIGH_RES_TIMERS enabled. Otherwise sleep
+timeout probably won't be able to calibrate itself and mptsd will not work.
+
 Documentation
 =============
 mptsd is controlled using command line parameters. Run mptsd to see all of

sleep.c

 	}
 
 	if (conf->output_tmout < 0) {
-		LOGf("usleep overhead is to much!! Disabling output rate control.\n");
+		LOGf("usleep overhead is too high! Make sure the kernel is compiled with CONFIG_HIGH_RES_TIMERS.\n");
 		conf->output_tmout = 0;
 	}