docs(arm): add to index and update Arm2D docs (#6768)

docs/integration/chip/arm.rst

@@ -47,7 +47,7 @@ To add Arm2D to your project, follow these steps:
 6. The CMSIS DSP library also needs to be added to the project. You can use CMSIS-PACKS or add it manually.
 7. For better performance, enable ``LTO`` (Link Time Optimization) and use ``-Omax`` or ``-Ofast``.
 8. Arm2D tries to read/write multiple data with a single instruction. Therefore, it's important to use the fastest memory (e.g., ``BSS`` or ``TCM``) for LVGL's buffer to avoid memory bandwidth bottlenecks.
-9. Enable ``LV_USE_DRAW_ARM2D_SYNC 1`` in ``lv_conf.h``.
+9. Enable ``LV_USE_DRAW_ARM2D_SYNC 1`` and ``LV_USE_DRAW_SW_ASM LV_DRAW_SW_ASM_HELIUM`` in ``lv_conf.h``.
 
 Neon Acceleration
 -----------------

docs/integration/chip/index.rst

@@ -9,3 +9,4 @@ Chip vendors
     nxp
     renesas
     stm32
+    arm