init shmem early to avoid random crash in fastrpc (#6407)

* init shmem early to avoid possible crash

* fix_code_style

* Keep the initialziation to NULL, remove the duplicate memory allocation

src/modules/muorb/adsp/px4muorb.cpp

@@ -56,6 +56,7 @@ __END_DECLS
 int px4muorb_orb_initialize()
 {
 	HAP_power_request(100, 100, 1000);
+	shmem_info_p = NULL;
 
 	// The uORB Manager needs to be initialized first up, otherwise the instance is nullptr.
 	uORB::Manager::initialize();