add a -vga none cli option (Stefano Stabellini)

currently there is no way to fully disable any graphic card device for
the PC architecture.
You can have no graphical output, thanks to -nographic, but you would
have the VGA device connected to your PCI bus anyway.
There is already a convenient -vga option to choose between std, cirrus
and vmware; this patch add the new option "none" to select no graphic
card at all.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6322 c046a42c-6fe2-441c-8c8c-71466251a162
diff --git a/vl.c b/vl.c
index f0701da..b35d740 100644
--- a/vl.c
+++ b/vl.c
@@ -192,6 +192,7 @@
 static int rtc_utc = 1;
 static int rtc_date_offset = -1; /* -1 means no change */
 int cirrus_vga_enabled = 1;
+int std_vga_enabled = 0;
 int vmsvga_enabled = 0;
 #ifdef TARGET_SPARC
 int graphic_width = 1024;
@@ -3873,7 +3874,7 @@
            "                use -soundhw ? to get the list of supported cards\n"
            "                use -soundhw all to enable all of them\n"
 #endif
-           "-vga [std|cirrus|vmware]\n"
+           "-vga [std|cirrus|vmware|none]\n"
            "                select video card type\n"
            "-localtime      set the real time clock to local time [default=utc]\n"
            "-full-screen    start in full screen\n"
@@ -4407,14 +4408,21 @@
     const char *opts;
 
     if (strstart(p, "std", &opts)) {
+        std_vga_enabled = 1;
         cirrus_vga_enabled = 0;
         vmsvga_enabled = 0;
     } else if (strstart(p, "cirrus", &opts)) {
         cirrus_vga_enabled = 1;
+        std_vga_enabled = 0;
         vmsvga_enabled = 0;
     } else if (strstart(p, "vmware", &opts)) {
         cirrus_vga_enabled = 0;
+        std_vga_enabled = 0;
         vmsvga_enabled = 1;
+    } else if (strstart(p, "none", &opts)) {
+        cirrus_vga_enabled = 0;
+        std_vga_enabled = 0;
+        vmsvga_enabled = 0;
     } else {
     invalid_vga:
         fprintf(stderr, "Unknown vga type: %s\n", p);