dependencies/openmp: Don't special case OpenMP

Currently we specialcase OpenMP like we do threads, with a special
`need_openmp` method. This seems like a great idea, but doesn't work
out in practice, as well as it complicates the opemp
implementation. If GCC is built without opemp support for example, we
still add -fopenmp to the the command line, which results in
compilation errors.

This patch discards that and treats it like a normal dependency,
removes the need_openmp() method, and sets the compile_args attributes
from the compiler.

Fixes #5115

0 files changed, 0 insertions, 0 deletions