add documentation for to_syslog_facility_code vrl function

website/cue/reference/remap/functions/to_syslog_facility_code.cue

@@ -0,0 +1,35 @@
+package metadata
+
+remap: functions: to_syslog_facility_code: {
+	category:    "Convert"
+	description: """
+		Converts the `value`, a Syslog [facility keyword](\(urls.syslog_facility)), into a Syslog integer
+		facility code (`0` to `23`).
+		"""
+
+	arguments: [
+		{
+			name:        "value"
+			description: "The Syslog facility keyword to convert."
+			required:    true
+			type: ["string"]
+		},
+	]
+	internal_failure_reasons: [
+		"`value` is not a valid Syslog facility keyword.",
+	]
+	return: {
+		types: ["integer"]
+		rules: []
+	}
+
+	examples: [
+		{
+			title: "Coerce to Syslog facility code"
+			source: """
+				to_syslog_facility_code!("authpriv")
+				"""
+			return: 10
+		},
+	]
+}