build: mark git as optional dependency

[sudipm-mukherjee]

A minimum build enironments might not have git installed and the build fails.
Mark 'git' as optional so that bpfilter can be built from a tarball.

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[qdeslandes]

Hi @sudipm-mukherjee , thanks for doing this. Could you add a check after find_package(Git) and print a log (e.g. "git not found, using default project version ${DEFAULT_PROJECT_VERSION}") before returning if git is not found? Otherwise, the default 0.0.0 version could be confusing. Additionally, -DDEFAULT_PROJECT_VERSION=x.y.z can be used when running CMake to build without Git but with a valid version number (see bpfilter.spec).

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[sudipm-mukherjee]

Hi @sudipm-mukherjee , thanks for doing this. Could you add a check after find_package(Git) and print a log (e.g. "git not found, using default project version ${DEFAULT_PROJECT_VERSION}") before returning if git is not found? Otherwise, the default 0.0.0 version could be confusing. Additionally, -DDEFAULT_PROJECT_VERSION=x.y.z can be used when running CMake to build without Git but with a valid version number (see bpfilter.spec).

Thanks for checking. Changes done.
yeah, I noticed DEFAULT_PROJECT_VERSION after making other changes to set the version. :)

[qdeslandes]

LGTM, thanks for working on this! :D