ext: Update ext/sst/INSTALL.md

Currently, the installation instructions are for installing
SST-core and SST-elements version 11.0.0. This change updates
instructions to the current SST-core and SST-element version,
11.1.0.

This change also reflects that manually downloading the
`bbl-busybox-boot-exit` is no longer necessary as the example
gem5 config will download automatically.

Change-Id: I616ca38316213dcbd71b6eab121b5ac89eed1962
Signed-off-by: Hoa Nguyen <hoanguyen@ucdavis.edu>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/53463
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
1 file changed