meson.build: convert --with-default-devices to meson

Pass the boolean option directly instead of writing
CONFIG_MINIKCONF_MODE to config-host.mak.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/meson.build b/meson.build
index ea2a2a9..dd61890 100644
--- a/meson.build
+++ b/meson.build
@@ -1284,7 +1284,8 @@
       output: config_devices_mak,
       depfile: config_devices_mak + '.d',
       capture: true,
-      command: [minikconf, config_host['CONFIG_MINIKCONF_MODE'],
+      command: [minikconf,
+                get_option('default_devices') ? '--defconfig' : '--allnoconfig',
                 config_devices_mak, '@DEPFILE@', '@INPUT@',
                 host_kconfig, accel_kconfig])
 
@@ -2478,7 +2479,7 @@
 summary_info += {'libpmem support':   config_host.has_key('CONFIG_LIBPMEM')}
 summary_info += {'libdaxctl support': config_host.has_key('CONFIG_LIBDAXCTL')}
 summary_info += {'libudev':           libudev.found()}
-summary_info += {'default devices':   config_host['CONFIG_MINIKCONF_MODE'] == '--defconfig'}
+summary_info += {'default devices':   get_option('default_devices')}
 summary_info += {'plugin support':    config_host.has_key('CONFIG_PLUGIN')}
 summary_info += {'fuzzing support':   config_host.has_key('CONFIG_FUZZ')}
 if config_host.has_key('HAVE_GDB_BIN')