qemu-iotests: Quote $TEST_IMG* and $TEST_DIR usage

A lot of image filename and paths are used unquoted.  Quote these to
make sure that directories / filenames with spaces are not problematic.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/tests/qemu-iotests/051 b/tests/qemu-iotests/051
index 78e1182..356c375 100755
--- a/tests/qemu-iotests/051
+++ b/tests/qemu-iotests/051
@@ -72,10 +72,10 @@
 echo === Unknown option ===
 echo
 
-run_qemu -drive file=$TEST_IMG,format=qcow2,unknown_opt=
-run_qemu -drive file=$TEST_IMG,format=qcow2,unknown_opt=on
-run_qemu -drive file=$TEST_IMG,format=qcow2,unknown_opt=1234
-run_qemu -drive file=$TEST_IMG,format=qcow2,unknown_opt=foo
+run_qemu -drive file="$TEST_IMG",format=qcow2,unknown_opt=
+run_qemu -drive file="$TEST_IMG",format=qcow2,unknown_opt=on
+run_qemu -drive file="$TEST_IMG",format=qcow2,unknown_opt=1234
+run_qemu -drive file="$TEST_IMG",format=qcow2,unknown_opt=foo
 
 echo
 echo === Overriding backing file ===
@@ -87,11 +87,11 @@
 echo === Enable and disable lazy refcounting on the command line, plus some invalid values ===
 echo
 
-run_qemu -drive file=$TEST_IMG,format=qcow2,lazy-refcounts=on
-run_qemu -drive file=$TEST_IMG,format=qcow2,lazy-refcounts=off
-run_qemu -drive file=$TEST_IMG,format=qcow2,lazy-refcounts=
-run_qemu -drive file=$TEST_IMG,format=qcow2,lazy-refcounts=42
-run_qemu -drive file=$TEST_IMG,format=qcow2,lazy-refcounts=foo
+run_qemu -drive file="$TEST_IMG",format=qcow2,lazy-refcounts=on
+run_qemu -drive file="$TEST_IMG",format=qcow2,lazy-refcounts=off
+run_qemu -drive file="$TEST_IMG",format=qcow2,lazy-refcounts=
+run_qemu -drive file="$TEST_IMG",format=qcow2,lazy-refcounts=42
+run_qemu -drive file="$TEST_IMG",format=qcow2,lazy-refcounts=foo
 
 
 echo
@@ -100,8 +100,8 @@
 
 _make_test_img -ocompat=0.10 $size
 
-run_qemu -drive file=$TEST_IMG,format=qcow2,lazy-refcounts=on
-run_qemu -drive file=$TEST_IMG,format=qcow2,lazy-refcounts=off
+run_qemu -drive file="$TEST_IMG",format=qcow2,lazy-refcounts=on
+run_qemu -drive file="$TEST_IMG",format=qcow2,lazy-refcounts=off
 
 echo
 echo === No medium ===
@@ -127,21 +127,21 @@
 echo === Read-only ===
 echo
 
-run_qemu -drive file=$TEST_IMG,if=floppy,readonly=on
-run_qemu -drive file=$TEST_IMG,if=ide,media=cdrom,readonly=on
-run_qemu -drive file=$TEST_IMG,if=scsi,media=cdrom,readonly=on
+run_qemu -drive file="$TEST_IMG",if=floppy,readonly=on
+run_qemu -drive file="$TEST_IMG",if=ide,media=cdrom,readonly=on
+run_qemu -drive file="$TEST_IMG",if=scsi,media=cdrom,readonly=on
 
-run_qemu -drive file=$TEST_IMG,if=ide,readonly=on
-run_qemu -drive file=$TEST_IMG,if=virtio,readonly=on
-run_qemu -drive file=$TEST_IMG,if=scsi,readonly=on
+run_qemu -drive file="$TEST_IMG",if=ide,readonly=on
+run_qemu -drive file="$TEST_IMG",if=virtio,readonly=on
+run_qemu -drive file="$TEST_IMG",if=scsi,readonly=on
 
-run_qemu -drive file=$TEST_IMG,if=none,id=disk,readonly=on -device ide-cd,drive=disk
-run_qemu -drive file=$TEST_IMG,if=none,id=disk,readonly=on -device lsi53c895a -device scsi-cd,drive=disk
+run_qemu -drive file="$TEST_IMG",if=none,id=disk,readonly=on -device ide-cd,drive=disk
+run_qemu -drive file="$TEST_IMG",if=none,id=disk,readonly=on -device lsi53c895a -device scsi-cd,drive=disk
 
-run_qemu -drive file=$TEST_IMG,if=none,id=disk,readonly=on -device ide-drive,drive=disk
-run_qemu -drive file=$TEST_IMG,if=none,id=disk,readonly=on -device ide-hd,drive=disk
-run_qemu -drive file=$TEST_IMG,if=none,id=disk,readonly=on -device lsi53c895a -device scsi-disk,drive=disk
-run_qemu -drive file=$TEST_IMG,if=none,id=disk,readonly=on -device lsi53c895a -device scsi-hd,drive=disk
+run_qemu -drive file="$TEST_IMG",if=none,id=disk,readonly=on -device ide-drive,drive=disk
+run_qemu -drive file="$TEST_IMG",if=none,id=disk,readonly=on -device ide-hd,drive=disk
+run_qemu -drive file="$TEST_IMG",if=none,id=disk,readonly=on -device lsi53c895a -device scsi-disk,drive=disk
+run_qemu -drive file="$TEST_IMG",if=none,id=disk,readonly=on -device lsi53c895a -device scsi-hd,drive=disk
 
 echo
 echo === Cache modes ===
@@ -161,8 +161,8 @@
 echo === Specifying the protocol layer ===
 echo
 
-run_qemu -drive file=$TEST_IMG,file.driver=file
-run_qemu -drive file=$TEST_IMG,file.driver=qcow2
+run_qemu -drive file="$TEST_IMG",file.driver=file
+run_qemu -drive file="$TEST_IMG",file.driver=qcow2
 
 echo
 echo === Parsing protocol from file name ===