buf_wren stays asserted during EXEC_WAIT state in ntt_ctrl module

[batthineniatlubis]

The issue here is, buf_wren stays high even in EXEC_WAIT(last state before going to STAGE state for next round) state and it writes 0s to the lower buffer while upper buffer is being read. This is not expected.

[upadhyayulakiran]

This is an issue, however in ABR we don't see functional issue due to this, since the 0s are written after the last set of writes complete. So, the 0s are never read and everything pointers are reset before starting next round. It's good to fix, but not a functional issue. Marking as enhancement