The ABI of libzfs and libzpool have breaking changes since the
last major release. Bump the SONAME for the upcoming 2.4 release
branch to libzfs7 and libzpool7.
Reviewed-by: Rob Norris <robn@despairlabs.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#17911
