s390x: switch boards to "default y"

Some targets use "default y" for boards to filter out those that require
TCG.  For consistency we are switching all other targets to do the same.
Continue with s390.

No changes to generated config-devices.mak file.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

.gitlab-ci.d/buildtest.yml

@@ -650,7 +650,7 @@ build-tci:
 # Check our reduced build configurations
 # requires libfdt: aarch64, arm, i386, loongarch64, microblaze, microblazeel,
 #   mips64el, or1k, ppc, ppc64, riscv32, riscv64, rx, x86_64
-# does not build without boards: i386, loongarch64, x86_64
+# does not build without boards: i386, loongarch64, s390x, x86_64
 build-without-defaults:
   extends: .native_build_job_template
   needs:
@@ -666,7 +666,7 @@ build-without-defaults:
       --disable-strip
     TARGETS: alpha-softmmu avr-softmmu cris-softmmu hppa-softmmu m68k-softmmu
       mips-softmmu mips64-softmmu mipsel-softmmu
-      s390x-softmmu sh4-softmmu
+      sh4-softmmu
       sparc64-softmmu hexagon-linux-user i386-linux-user s390x-linux-user
     MAKE_CHECK_ARGS: check
 

configs/devices/s390x-softmmu/default.mak

@@ -9,6 +9,5 @@
 #CONFIG_WDT_DIAG288=n
 #CONFIG_PCIE_DEVICES=n
 
-# Boards:
-#
-CONFIG_S390_CCW_VIRTIO=y
+# Boards are selected by default, uncomment to keep out of the build.
+# CONFIG_S390_CCW_VIRTIO=n

hw/s390x/Kconfig

@@ -1,5 +1,7 @@
 config S390_CCW_VIRTIO
     bool
+    default y
+    depends on S390X
     imply VIRTIO_PCI
     imply TERMINAL3270
     imply VFIO_AP