Remove unused variables

The `LED_JSON_FILE` variable declared in meson.build has been
deprecated and replaced by `confBasePath`[1].

[1] https://github.com/openbmc/phosphor-led-manager/commit/616a0716970203cb77dc92301f0763043c5b461c#diff-6d7dfec73b9c66c317e9bfab43d3320b2133bf883674773fd467a99888896ff5R21

Signed-off-by: George Liu <liuxiwei@ieisystem.com>
Change-Id: Ia78cdf51843d90b7c7495ac4688c45a208600550
diff --git a/meson.build b/meson.build
index 93a2177..20f718b 100644
--- a/meson.build
+++ b/meson.build
@@ -13,7 +13,6 @@
 cpp = meson.get_compiler('cpp')
 
 conf_data = configuration_data()
-conf_data.set_quoted('LED_JSON_FILE', '/usr/share/phosphor-led-manager/led-group-config.json')
 conf_data.set_quoted('SAVED_GROUPS_FILE', '/var/lib/phosphor-led-manager/savedGroups')
 conf_data.set_quoted('CALLOUT_FWD_ASSOCIATION', 'callout')
 conf_data.set_quoted('CALLOUT_REV_ASSOCIATION', 'fault')