Updates to fix (and improve) the UI handling of the emulated keyboard state.

Updatd mem.c with new readmem386l and writemem386l functions from 86Box.
Several cleanups to the keyboard layer to remove some weirdness.
Updated the NVR code and nvr_at.c to just use a speed_changed member for the AT devices.

src/pc.c

@@ -8,7 +8,7 @@
  *
  *		Main emulator module where most things are controlled.
  *
- * Version:	@(#)pc.c	1.0.69	2019/04/23
+ * Version:	@(#)pc.c	1.0.71	2019/04/26
  *
  * Authors:	Fred N. van Kempen, <decwiz@yahoo.com>
  *		Miran Grca, <mgrca8@gmail.com>
@@ -798,7 +798,6 @@ INFO("PC: set_speed(%i) -> speed %lu\n", turbo, speed);
      * timer system is built around the CPU clock as a
      * base unit. So, if we change that, everything does..
      */
-    nvr_period_recalc();
 }
 
 
@@ -910,7 +909,6 @@ pc_init(void)
 
     timer_reset();
 
-    keyboard_init();
     joystick_init();
 
     video_init();
@@ -1037,8 +1035,8 @@ pc_reset_hard_init(void)
     isartc_reset();
 
     /* Reset some basic devices. */
-    mouse_reset();
     keyboard_reset();
+    mouse_reset();
 
     /* Reset sound system. This MAY add a game port, so before joystick! */
     sound_reset();