Add RISCV env variable to Getting Started

README.md

@@ -58,6 +58,7 @@ These instructions assume you have the [LLVM Xposit](https://github.com/artecs-g
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 sudo apt install -y git curl gcc g++ make autoconf
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+Make sure you have the $RISCV environment variable pointing to the directory where you installed the RISC-V gcc toolchain. E.g. `export RISCV="/opt/riscv`. Consider adding this permanently in your `.bashrc` file.
 
 ### Checkout the repository
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