Update dynamic arch list to new target scheme

Author: martin-frbg

cmake/arch.cmake

@@ -95,7 +95,7 @@ if (DYNAMIC_ARCH)
   endif ()
 
   if (LOONGARCH64)
-    set(DYNAMIC_CORE LOONGSONGENERIC LOONGSON2K1000 LOONGSON3R5)
+    set(DYNAMIC_CORE LA64_GENERIC LA264 LA464)
   endif ()
 
   if (EXISTS ${PROJECT_SOURCE_DIR}/config_kernel.h)