add firmware to machine options

This patch adds firmware to the machine options.  -bios <file> becomes a
shortcut for -machine firmware=<file>.  Advantage is that the firmware
can be specified via config file as -machine is parsed using QemuOpts
and it is also possible to use different defaults for different
machine types (via QEMUMachine->default_machine_opts).
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

vl.c

@@ -428,6 +428,10 @@ static QemuOptsList qemu_machine_opts = {
             .name = "usb",
             .type = QEMU_OPT_BOOL,
             .help = "Set on/off to enable/disable usb",
+        },{
+            .name = "firmware",
+            .type = QEMU_OPT_STRING,
+            .help = "firmware image",
         },
         { /* End of list */ }
     },
@@ -3229,7 +3233,7 @@ int main(int argc, char **argv, char **envp)
                 }
                 break;
             case QEMU_OPTION_bios:
-                bios_name = optarg;
+                qemu_opts_set(qemu_find_opts("machine"), 0, "firmware", optarg);
                 break;
             case QEMU_OPTION_singlestep:
                 singlestep = 1;
@@ -4050,6 +4054,7 @@ int main(int argc, char **argv, char **envp)
     kernel_filename = qemu_opt_get(machine_opts, "kernel");
     initrd_filename = qemu_opt_get(machine_opts, "initrd");
     kernel_cmdline = qemu_opt_get(machine_opts, "append");
+    bios_name = qemu_opt_get(machine_opts, "firmware");
 
     boot_order = machine->default_boot_order;
     opts = qemu_opts_find(qemu_find_opts("boot-opts"), NULL);