prep a fork of riscv package

for now, publish a xous-riscv package, until we can absorb
this into the kernel directly.

Want to recode all the assembly files into inline-assembly now
that it is supported in Rust, but, let's not put that yak on
the list of yaks to shave before we have a separable kernel.

imports/riscv-0.5.6/Cargo.toml

@@ -1,10 +1,10 @@
 [package]
-name = "riscv"
+name = "xous-riscv"
 version = "0.5.6"
 repository = "https://github.com/rust-embedded/riscv"
 authors = ["The RISC-V Team <risc-v@teams.rust-embedded.org>"]
 categories = ["embedded", "hardware-support", "no-std"]
-description = "Low level access to RISC-V processors"
+description = "Low level access to RISC-V processors; Xous fork"
 keywords = ["riscv", "register", "peripheral"]
 license = "ISC"