build: use allowed over enabled

Meson feature options are typically in a tri-state of enabled, disabled,
or auto.  The enabled and disabled functions on an option (from
`get_option`) no longer return true for auto features.  Instead, the
expectation is to use `allowed()` which is true for both enabled and auto.

Switch all uses of `enabled` to `allowed`.

Change-Id: I4db060ea85cfae7be96693ec04a09829767351a1
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/manager/meson.build b/manager/meson.build
index b3eddeb..e2452bd 100644
--- a/manager/meson.build
+++ b/manager/meson.build
@@ -19,7 +19,7 @@
     sources += [led_gen_hpp]
 endif
 
-if get_option('use-lamp-test').enabled()
+if get_option('use-lamp-test').allowed()
     conf_data.set_quoted('LAMP_TEST_OBJECT', '/xyz/openbmc_project/led/groups/lamp_test')
     conf_data.set_quoted('HOST_LAMP_TEST_OBJECT', '/xyz/openbmc_project/led/groups/host_lamp_test')
     conf_data.set_quoted('LAMP_TEST_LED_OVERRIDES_JSON', '/usr/share/phosphor-led-manager/lamp-test-led-overrides.json')