[docs] Add vector predication call

[simoll]

Summary

Add the syncup call to the table

[craig.topper]

LGTM

[vkmr]

@simoll thanks for putting this up. Wondering if this would be the right place to add a link to the discord channel too!

[simoll]

Thanks. I am not too excited to moderate an open Discord server. Better invite people individually / on the call.

llvm/docs/GettingInvolved.rst

.. list-table:: LLVM regular sync-up calls
    * - LLVM Alias Analysis
      - Every 4 weeks on Tuesdays
      - `ics <http://lists.llvm.org/pipermail/llvm-dev/attachments/20201103/a3499a67/attachment-0001.ics>`__
      - `Minutes/docs <https://docs.google.com/document/d/17U-WvX8qyKc3S36YUKr3xfF-GHunWyYowXbxEdpHscw>`__
    * - Windows/COFF related developments
      - Every 2 months on Thursday
      - 
      - `Minutes/docs <https://docs.google.com/document/d/1A-W0Sas_oHWTEl_x_djZYoRtzAdTONMW_6l1BH9G6Bo/edit?usp=sharing>`__
-
+   * - Vector Predication
+     - Every 2 weeks on Tuesdays, 3pm UTC
+     -
+     - `Minutes/docs <https://docs.google.com/document/d/1q26ToudQjnqN5x31zk8zgq_s0lem1-BF8pQmciLa4k8/edit?usp=sharing>`__
 
 IRC
 ---
 
 Users and developers of the LLVM project (including subprojects such as Clang)
 can be found in #llvm on `irc.oftc.net <irc://irc.oftc.net/llvm>`_.
 
 This channel has several bots.