Convert Solaris #ifdef's for <sys/kd.h> to AC_CHECK_HEADERS check

Upcoming virtual terminal support changes in Solaris kernel will provide
<sys/kd.h> on SPARC too, so this gets us ready for them.

configure.ac

@@ -1280,6 +1280,7 @@ if test "x$XORG" = xyes; then
 	  solaris*)
 	  	XORG_OS="solaris"
 		XORG_OS_SUBDIR="solaris"
+		AC_CHECK_HEADERS([sys/kd.h])
 		# This really should be tests for specific features, but the #ifdef's
 		# were done as a simple version check in XFree86 4.x and haven't been 
 		# fixed yet

hw/xfree86/os-support/solaris/sun_init.c

@@ -29,7 +29,7 @@
 #include "xf86.h"
 #include "xf86Priv.h"
 #include "xf86_OSlib.h"
-#if defined(__i386__) || defined(__i386) || defined(__x86)
+#ifdef HAVE_SYS_KD_H
 # include <sys/kd.h>
 #endif
 

include/xorg-config.h.in

@@ -54,6 +54,9 @@
 /* Solaris 8 or later? */
 #undef __SOL8__
 
+/* Define to 1 if you have the <sys/kd.h> header file. */
+#undef HAVE_SYS_KD_H
+
 /* Define to 1 if you have the `walkcontext' function (used on Solaris for
    xorg_backtrace in hw/xfree86/common/xf86Events.c */
 #undef HAVE_WALKCONTEXT