Expose BEYLA_BPF_FS_PATH in Alloy

[mariomac]

trafficstars

A customer would like to use Beyla from Alloy, without system administrator capabilities. For that, we must mount the BPF FS externally and pass the custom mount as BEYLA_BPF_FS_PATH.

[rafaelroquetto]

We might also want to expose BEYLA_BPF_FS_BASE_DIR if that is not yet the case.

[marctc]

I believe we won't need this anymore