tests/qtest: Don't run cdrom tests if no accelerator is present

On a build configured with: --disable-tcg --enable-xen it is possible
to produce a QEMU binary with no TCG nor KVM support. Skip the test if
that's the case.

Fixes: 0c1ae3ff9d ("tests/qtest: Fix tests when no KVM or TCG are present")
Signed-off-by: Fabiano Rosas <farosas@suse.de>

target/arm/Kconfig

@@ -1,13 +1,8 @@
 config ARM
     bool
+    select ARM_COMPATIBLE_SEMIHOSTING if TCG
+    select ARM_V7M if TCG
 
 config AARCH64
     bool
     select ARM
-
-# This config exists just so we can make SEMIHOSTING default when TCG
-# is selected without also changing it for other architectures.
-config ARM_SEMIHOSTING
-    bool
-    default y if TCG && ARM
-    select ARM_COMPATIBLE_SEMIHOSTING

tests/qtest/cdrom-test.c

@@ -130,6 +130,11 @@ static void test_cdboot(gconstpointer data)
 
 static void add_x86_tests(void)
 {
+    if (!qtest_has_accel("tcg") && !qtest_has_accel("kvm")) {
+        g_test_skip("No KVM or TCG accelerator available, skipping boot tests");
+        return;
+    }
+
     qtest_add_data_func("cdrom/boot/default", "-cdrom ", test_cdboot);
     qtest_add_data_func("cdrom/boot/virtio-scsi",
                         "-device virtio-scsi -device scsi-cd,drive=cdr "
@@ -176,6 +181,11 @@ static void add_x86_tests(void)
 
 static void add_s390x_tests(void)
 {
+    if (!qtest_has_accel("tcg") && !qtest_has_accel("kvm")) {
+        g_test_skip("No KVM or TCG accelerator available, skipping boot tests");
+        return;
+    }
+
     qtest_add_data_func("cdrom/boot/default", "-cdrom ", test_cdboot);
     qtest_add_data_func("cdrom/boot/virtio-scsi",
                         "-device virtio-scsi -device scsi-cd,drive=cdr "