dockerfile changes

xc7/Dockerfile

@@ -1,24 +1,5 @@
 FROM ubuntu:18.04
 
- # RISC-V toolchain
-RUN apt-get update && apt-get install -y software-properties-common make verilog autoconf automake autotools-dev curl libmpc-dev \
-    libmpfr-dev libgmp-dev gawk build-essential bison flex texinfo \
-    gperf libtool patchutils bc zlib1g-dev git libexpat1-dev
-
-RUN mkdir /opt/riscv32i \
-&& git clone https://github.com/riscv/riscv-gnu-toolchain riscv-gnu-toolchain-rv32i \
-&& cd riscv-gnu-toolchain-rv32i \
-&& git checkout 411d134 \
-&& git submodule update --init --recursive
-
-RUN cd riscv-gnu-toolchain-rv32i && mkdir build \
-&& cd build \
-&& ../configure --with-arch=rv32i --prefix=/opt/riscv32i \
-&& make -j$(nproc)
-
-ENV PATH="$PATH:/opt/riscv32i/bin"
-
-# Symbilflow
 
 ARG INSTALL_DIR=/root/opt/symbiflow
 ARG FPGA_FAM=xc7