This commit adds additional information to the output_env.sh script of:
* Linux distribution version (if available)
* GDB version (if available)
It also makes some information clearer:
* the type of OpenSSL/GNUTLS version (legacy/default/next)
* and whether certain versions are not installed, or not configured
And it simplifies the error messages for absent tools.
Signed-off-by: Simon Butcher <simon.butcher@arm.com>