libyang REFACTOR rename LY_PREFIX_FORMAT values

Reflect that the value format is the primary concern of the enum, the prefix
interpretation is only based on the format.
diff --git a/src/schema_compile.h b/src/schema_compile.h
index 6fc060f..c3adbff 100644
--- a/src/schema_compile.h
+++ b/src/schema_compile.h
@@ -235,7 +235,7 @@
  * @return LY_SUCCESS on success.
  * @return LY_ERR on error.
  */
-LY_ERR lys_compile_expr_implement(const struct ly_ctx *ctx, const struct lyxp_expr *expr, LY_PREFIX_FORMAT format,
+LY_ERR lys_compile_expr_implement(const struct ly_ctx *ctx, const struct lyxp_expr *expr, LY_VALUE_FORMAT format,
         void *prefix_data, ly_bool implement, struct lys_glob_unres *unres, const struct lys_module **mod_p);
 
 /**