meson: Add some compiler options

I got caught out by CI using stricter configuration, so add CI's
configuration as the default set of options to meson.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Change-Id: I6932a231d2162de751eb5dd49b1abfdd97a0eb1d
diff --git a/meson.build b/meson.build
index ebd77b6..96f437e 100644
--- a/meson.build
+++ b/meson.build
@@ -1,4 +1,11 @@
-project('debug-trigger', 'c', license: 'Apache-2.0', version: '0.1')
+project('debug-trigger', 'c',
+	license: 'Apache-2.0',
+	version: '0.1',
+	default_options: [
+		'warning_level=3',
+		'werror=true',
+		'c_std=gnu18',
+	])
 executable('debug-trigger', 'main.c', install: true)
 
 if get_option('systemd')