[Chapel Merge] Discontinue use of the fallback "system" libfabric

Branch: refs/heads/main
Revision: 4c98fd3
Author: gbtitus
Link: Discontinue use of the fallback "system" libfabric install for EX builds. by gbtitus · Pull Request #19394 · chapel-lang/chapel · GitHub
Log Message:

Merge pull request #19394 from gbtitus/rm-fallback-system-libfabric

Discontinue use of the fallback "system" libfabric install for EX builds.

(Reviewed by @ronawho and @soohoonchoi.)

We've been maintaining a fallback "system" libfabric install on a widely
shared filesystem. The HPE Cray EX module build was using that fallback
if pkg-config didn't already know about a real libfabric install. But
that only happened when we built the EX module on an XC system, and we
stopped doing that quite a while ago. Now we always build for the EX in
a virtual environment which doesn't even mount that shared filesystem.
Therefore here, get rid of all the logic associated with the fallback
"system" libfabric install.

Modified Files:
M util/build_configs/cray-internal/setenv-hpe-cray-ex-x86_64.bash

Compare: https://github.com/chapel-lang/chapel/compare/d22161b4ea81...4c98fd3ac119