[PATCH 1/6] RISC-V: Fix libnosys build

[Jim Wilson]

FYI Patches 2 through 6 are already in the github riscv/riscv-newlib 
tree, which is the tree that most RISC-V developers currently use, via 
the riscv/riscv-gnu-toolchain project.  It would be good to have them in 
the upstream sourceware.org tree too for consistency.  I'm trying to do 
as much work as possible in the upstream trees, but missing patches make 
this tricky.  Patch 1 appears to be new.  The patches all look 
reasonable to me.  Patch 5 can work only if patch 6 is also added.  This 
was a mistake on my part, not understanding how git submodule worked at 
the time, and hence not realizing that I didn't have the most recent 
version of the sources checked out.

Jim