m68k: 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 m68k.

No changes to generated config-devices.mak file.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/.gitlab-ci.d/buildtest.yml b/.gitlab-ci.d/buildtest.yml
index a82848b..a91e8d3 100644
--- a/.gitlab-ci.d/buildtest.yml
+++ b/.gitlab-ci.d/buildtest.yml
@@ -663,7 +663,7 @@
       --disable-pie
       --disable-qom-cast-debug
       --disable-strip
-    TARGETS: alpha-softmmu avr-softmmu cris-softmmu hppa-softmmu
+    TARGETS: alpha-softmmu avr-softmmu cris-softmmu hppa-softmmu m68k-softmmu
       s390x-softmmu sh4-softmmu
       sparc64-softmmu hexagon-linux-user i386-linux-user s390x-linux-user
     MAKE_CHECK_ARGS: check
diff --git a/configs/devices/m68k-softmmu/default.mak b/configs/devices/m68k-softmmu/default.mak
index 8dcaa28..3ceda6b 100644
--- a/configs/devices/m68k-softmmu/default.mak
+++ b/configs/devices/m68k-softmmu/default.mak
@@ -1,9 +1,8 @@
 # Default configuration for m68k-softmmu
 
-# Boards:
-#
-CONFIG_AN5206=y
-CONFIG_MCF5208=y
-CONFIG_NEXTCUBE=y
-CONFIG_Q800=y
-CONFIG_M68K_VIRT=y
+# Boards are selected by default, uncomment to keep out of the build.
+# CONFIG_AN5206=n
+# CONFIG_MCF5208=n
+# CONFIG_NEXTCUBE=n
+# CONFIG_Q800=n
+# CONFIG_M68K_VIRT=n
diff --git a/hw/m68k/Kconfig b/hw/m68k/Kconfig
index d88741e..0092cda 100644
--- a/hw/m68k/Kconfig
+++ b/hw/m68k/Kconfig
@@ -1,20 +1,28 @@
 config AN5206
     bool
+    default y
+    depends on M68K
     select COLDFIRE
     select PTIMER
 
 config MCF5208
     bool
+    default y
+    depends on M68K
     select COLDFIRE
     select PTIMER
 
 config NEXTCUBE
     bool
+    default y
+    depends on M68K
     select FRAMEBUFFER
     select ESCC
 
 config Q800
     bool
+    default y
+    depends on M68K
     select MAC_VIA
     select NUBUS
     select MACFB
@@ -29,6 +37,8 @@
 
 config M68K_VIRT
     bool
+    default y
+    depends on M68K
     select M68K_IRQC
     select VIRT_CTRL
     select GOLDFISH_PIC