Add clangNosvOpenmp-ld compiler test

Add a test to verify that "clang -fopenmp=libompv" links correctly with
nOS-V even though it is not placed in the buildInputs.

Reviewed-by: Aleix Roca Nonell <aleix.rocanonell@bsc.es>
Reviewed-by: Rodrigo Arias Mallo <rodrigo.arias@bsc.es>
Tested-by: Rodrigo Arias Mallo <rodrigo.arias@bsc.es>