spirv: Add support for runtime descriptor array cap.

Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>

src/compiler/shader_info.h

@@ -54,6 +54,7 @@ struct spirv_supported_capabilities {
    bool gcn_shader;
    bool trinary_minmax;
    bool descriptor_array_dynamic_indexing;
+   bool runtime_descriptor_array;
 };
 
 typedef struct shader_info {

src/compiler/spirv/spirv_to_nir.c

@@ -3390,6 +3390,10 @@ vtn_handle_preamble_instruction(struct vtn_builder *b, SpvOp opcode,
          spv_check_supported(descriptor_array_dynamic_indexing, cap);
          break;
 
+      case SpvCapabilityRuntimeDescriptorArrayEXT:
+         spv_check_supported(runtime_descriptor_array, cap);
+         break;
+
       default:
          vtn_fail("Unhandled capability");
       }