fix(build): enable dynamic loading backend for Linux builds

Author: Gioee

.github/workflows/main.yml

@@ -18,11 +18,11 @@ jobs:
           - os: ubuntu-latest
             arch: x86_64
             name: linux
-            make: LLAMA="-DGGML_NATIVE=OFF -DGGML_CPU_ALL_VARIANTS=ON -DGGML_BLAS=ON -DGGML_BLAS_VENDOR=OpenBLAS -DGGML_VULKAN=ON -DGGML_OPENCL=ON"
+            make: LLAMA="-DGGML_NATIVE=OFF -DGGML_BACKEND_DL=ON -DGGML_CPU_ALL_VARIANTS=ON -DGGML_BLAS=ON -DGGML_BLAS_VENDOR=OpenBLAS -DGGML_VULKAN=ON -DGGML_OPENCL=ON"
           - os: LinuxARM64
             arch: arm64
             name: linux
-            make: LLAMA="-DGGML_NATIVE=OFF -DGGML_CPU_ALL_VARIANTS=ON -DGGML_BLAS=ON -DGGML_BLAS_VENDOR=OpenBLAS -DGGML_VULKAN=ON -DGGML_OPENCL=ON"
+            make: LLAMA="-DGGML_NATIVE=OFF -DGGML_BACKEND_DL=ON -DGGML_CPU_ALL_VARIANTS=ON -DGGML_BLAS=ON -DGGML_BLAS_VENDOR=OpenBLAS -DGGML_VULKAN=ON -DGGML_OPENCL=ON"
           - os: macos-latest
             name: macos
             make: LLAMA="-DGGML_NATIVE=ON -DGGML_METAL=ON -DGGML_ACCELERATE=ON -DGGML_BLAS=ON -DGGML_BLAS_VENDOR=Apple" WHISPER="-DGGML_METAL=ON -DGGML_ACCELERATE=ON -DGGML_BLAS=ON -DGGML_BLAS_VENDOR=Apple -DWHISPER_COREML=ON -DWHISPER_COREML_ALLOW_FALLBACK=ON"