xf86-video-ast: Changes to 'master'

[Y.C. Chen]

 configure.ac      |    2 
 src/ast.h         |   10 
 src/ast_driver.c  |  651 ++++++++++++++++++++++++++++++------------------------
 src/ast_mode.c    |   36 ++
 src/ast_mode.h    |    3 
 src/ast_vgatool.c |  135 +++++++++--
 src/ast_vgatool.h |   64 ++---
 7 files changed, 565 insertions(+), 336 deletions(-)

New commits:
commit dc971ee25afb462f871ba1fb93f3bc996540ef51
Author: Y.C. Chen <yc_chen at aspeedtech.com>
Date:   Tue Apr 3 18:00:50 2012 +0800

    fix segmentation fault issue if enable XEN