build-llvm: enable nvptx

Used to enable CUDA filter support for FFmpeg without relying on another Clang.

build-llvm.sh

@@ -308,7 +308,7 @@ cmake \
     -DCMAKE_BUILD_TYPE=Release \
     -DLLVM_ENABLE_ASSERTIONS=$ASSERTS \
     -DLLVM_ENABLE_PROJECTS="$PROJECTS" \
-    -DLLVM_TARGETS_TO_BUILD="ARM;AArch64;X86" \
+    -DLLVM_TARGETS_TO_BUILD="ARM;AArch64;X86;NVPTX" \
     -DLLVM_INSTALL_TOOLCHAIN_ONLY=$TOOLCHAIN_ONLY \
     -DLLVM_LINK_LLVM_DYLIB=$LINK_DYLIB \
     -DLLVM_TOOLCHAIN_TOOLS="llvm-ar;llvm-ranlib;llvm-objdump;llvm-rc;llvm-cvtres;llvm-nm;llvm-strings;llvm-readobj;llvm-dlltool;llvm-pdbutil;llvm-objcopy;llvm-strip;llvm-cov;llvm-profdata;llvm-addr2line;llvm-symbolizer;llvm-windres;llvm-ml;llvm-readelf;llvm-size;llvm-cxxfilt" \