ac/llvm: bump the number of results to 8.

This function can get access for a 64-bit dvec4, which means we
have to load 8 components.

This fixes:
R600_DEBUG=nir ./bin/shader_runner generated_tests/spec/arb_gpu_shader_fp64/execution/built-in-functions/fs-abs-dvec4.shader_test -auto

Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>

src/amd/common/ac_llvm_build.c

@@ -983,7 +983,7 @@ ac_build_buffer_load(struct ac_llvm_context *ctx,
 	if (allow_smem && !glc && !slc) {
 		assert(vindex == NULL);
 
-		LLVMValueRef result[4];
+		LLVMValueRef result[8];
 
 		for (int i = 0; i < num_channels; i++) {
 			if (i) {