virtual-machines: add -i/--install option for mounting installer images

scripts/fish/vm-qemu

@@ -1,10 +1,13 @@
 # vim: syntax=fish:
 
-function vm-qemu -d "Frontend to QEMU" -a cfg
+function vm-qemu -d "Frontend to QEMU"
+	set cfg $argv[1]
+	set -e argv[1]
 	env \
 		_vm_img="/mnt/s/vm/$cfg/image" \
 		_vm_media="/mnt/s/osmedia" \
 		_vm_setup="$_agw_dir_rc/virtual-machines/qemu-setup" \
+		_vm_args="$argv" \
 		$_agw_dir_rc/virtual-machines/$cfg/run
 end
 

virtual-machines/qemu-setup

@@ -1,5 +1,16 @@
 # vim: syntax=fish:
 
+for opt in $_vm_args
+	switch "$opt"
+		case ""
+		case -i --install
+			set _use_install 1
+		case \*
+			echo "error: unknown option $opt"
+			exit 1
+	end
+end
+
 set _boot_order c
 
 set _args \
@@ -12,7 +23,7 @@ if test $_arch = "i386" || test $_arch = "x86_64"
 		$_args
 end
 
-if test $_install
+if test $_install && test $_use_install
 	set _boot_order d
 	set _args \
 		--drive file="$_install",media=cdrom,readonly \