Add change about data vector types

docs/cs_v6_release_guide.md

@@ -50,6 +50,7 @@ We hope you enjoy the new release!
 | `writeback` | `writeback` member was moved to detail. |||
 | Register alias | Register alias (`r15 = pc` etc.) are not printed if LLVM doesn't do it. Old Capstone register alias can be enabled by `CS_OPT_SYNTAX_CS_REG_ALIAS`. | Mimic LLVM as close as possile. | Enable option. |
 | Immediate | Immediate values (`arm_op.imm`) type changed to `int64_t` |||
+| (Vector) data types | `arm.vector_data` is now of type `cs_data_type`. Old vector data types have been removed. | Data types in general now match the ones define in LLVM for comaptibility reasons. | None. |
 
 **PPC**