Update XRT_installation_instructions.md

update links for 2021.2

Author: kyyalama2

Vitis/docs/XRT_installation_instructions.md

@@ -6,6 +6,7 @@
 
 | Xilinx Vitis Tool Version | XRT Release Tag | SHA | `xrt` or `xrt-aws` RPM's (Centos/RHEL) |`xrt` or`xrt-aws` RPM's (AL2) |
 |---|---|---|---|---|
+|2021.2| [202120.2.12.427](https://github.com/Xilinx/XRT/releases/tag/202120.2.12.427) | 2719b6027e185000fc49783171631db03fc0ef79 | [xrt_202120.2.12.0_7.9.2009-x86_64-aws.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.12.0/Patches/XRT_2021_2/xrt_202120.2.12.0_7.9.2009-x86_64-aws.rpm) [xrt_202120.2.12.0_7.9.2009-x86_64-xrt.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.12.0/Patches/XRT_2021_2/xrt_202120.2.12.0_7.9.2009-x86_64-xrt.rpm) | [xrt_202210.2.13.0_2-x86_64-aws.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.12.0/Patches/XRT_2021_2/xrt_202210.2.13.0_2-x86_64-aws.rpm) [xrt_202210.2.13.0_2-x86_64-xrt.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.12.0/Patches/XRT_2021_2/xrt_202210.2.13.0_2-x86_64-xrt.rpm)|
 |2021.1| [202110.2.11.634](https://github.com/Xilinx/XRT/releases/tag/202110.2.11.634) | 5ad5998d67080f00bca5bf15b3838cf35e0a7b26 | [xrt_202110.2.11.0_7.9.2009-x86_64-xrt.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.11.0/Patches/XRT_2021_1/xrt_202110.2.11.0_7.9.2009-x86_64-xrt.rpm) [xrt_202110.2.11.0_7.9.2009-x86_64-aws.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.11.0/Patches/XRT_2021_1/xrt_202110.2.11.0_7.9.2009-x86_64-aws.rpm) | [xrt_202110.2.11.0_2-x86_64-xrt.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.11.0/Patches/XRT_2021_1/xrt_202110.2.11.0_2-x86_64-xrt.rpm) [xrt_202110.2.11.0_2-x86_64-aws.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.11.0/Patches/XRT_2021_1/xrt_202110.2.11.0_2-x86_64-aws.rpm)|
 |2020.2| [202020.2.8.743](https://github.com/Xilinx/XRT/releases/tag/202020.2.8.743) | 77d5484b5c4daa691a7f78235053fb036829b1e9 | [xrt_202020.2.8.0_7.9.2009-x86_64-xrt.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.10.0/Patches/XRT_2020_2/xrt_202020.2.8.0_7.9.2009-x86_64-xrt.rpm) [xrt_202020.2.8.0_7.9.2009-x86_64-aws.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.10.0/Patches/XRT_2020_2/xrt_202020.2.8.0_7.9.2009-x86_64-aws.rpm) | [xrt_202020.2.8.0_2-x86_64-xrt.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.10.0/Patches/XRT_2020_2/xrt_202020.2.8.0_2-x86_64-xrt.rpm) [xrt_202020.2.8.0_2-x86_64-aws.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.10.0/Patches/XRT_2020_2/xrt_202020.2.8.0_2-x86_64-aws.rpm)|
 |2020.1| [202010.2.6.AWS](https://github.com/Xilinx/XRT/releases/tag/202010.2.6.AWS) | d09c4a458c16e8d843b3165dcf929c38f7a32b6f | [xrt_202010.2.6.0_7.7.1908-x86_64-xrt.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.9.0/Patches/XRT_2020_1/xrt_202010.2.6.0_7.7.1908-x86_64-xrt.rpm) [xrt_202010.2.6.0_7.7.1908-x86_64-aws.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.9.0/Patches/XRT_2020_1/xrt_202010.2.6.0_7.7.1908-x86_64-aws.rpm) | [xrt_202010.2.6.0_2-x86_64-xrt.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.9.0/Patches/XRT_2020_1/xrt_202010.2.6.0_2-x86_64-xrt.rpm) [xrt_202010.2.6.0_2-x86_64-aws.rpm](https://aws-fpga-developer-ami.s3.amazonaws.com/1.9.0/Patches/XRT_2020_1/xrt_202010.2.6.0_2-x86_64-aws.rpm)|