Documentation: embargoed-hardware-issues.rst: Add myself for RISC-V

I'm not sure exactly how RISC-V fits into the story here, but I'm happy
to voluteer a sort of catch-all for vendors who aren't otherwise
represented.

Signed-off-by: Palmer Dabbelt <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: palmer-dabbelt

Documentation/process/embargoed-hardware-issues.rst

@@ -251,6 +251,7 @@ an involved disclosed party. The current ambassadors list:
   IBM Z		Christian Borntraeger <[email protected]>
   Intel		Tony Luck <[email protected]>
   Qualcomm	Trilok Soni <[email protected]>
+  RISC-V	Palmer Dabbelt <[email protected]>
   Samsung	Javier González <[email protected]>
 
   Microsoft	James Morris <[email protected]>