Wasm-wc: Add core configuration data structure

This is required to actually _build_ the 'wasm-wasi-componet' language
module.

The nxt_wasm_wc_app_conf_t structure consists of the component name, e.g
my_component.wasm, this is required. It also consists of an object to
store the directories that are allowed access to by the component, this
is optional.

The bulk of the configuration infrastructure will be added in a
subsequent commit.

Signed-off-by: Andrew Clayton <a.clayton@nginx.com>

src/nxt_application.h

@@ -105,6 +105,13 @@ typedef struct {
 } nxt_wasm_app_conf_t;
 
 
+typedef struct {
+    const char        *component;
+
+    nxt_conf_value_t  *access;
+} nxt_wasm_wc_app_conf_t;
+
+
 struct nxt_common_app_conf_s {
     nxt_str_t                  name;
     nxt_str_t                  type;
@@ -134,6 +141,7 @@ struct nxt_common_app_conf_s {
         nxt_ruby_app_conf_t      ruby;
         nxt_java_app_conf_t      java;
         nxt_wasm_app_conf_t      wasm;
+        nxt_wasm_wc_app_conf_t   wasm_wc;
     } u;
 
     nxt_conf_value_t           *self;