Move get_bool() to src/common/

...in preparation for sharing it more widely

include/common/get-bool.h

@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __LABWC_GET_BOOL_H
+#define __LABWC_GET_BOOL_H
+#include <stdbool.h>
+
+/**
+ * get_bool - interpret string and return boolean
+ * @s: string to interpret
+ *
+ * Note: This merely performs a case-insensitive check for 'yes' and 'true'.
+ * Returns false by default.
+ */
+bool get_bool(const char *s);
+
+#endif /* __LABWC_GET_BOOL_H */