[flang][NFC] turn fir.call is_bind_c into enum for procedure flags (#105691)

First patch to fix a BIND(C) ABI issue
(https://github.com/llvm/llvm-project/issues/102113). I need to keep
track of BIND(C) in more locations (fir.dispatch and func.func
operations), and I need to fix a few passes that are dropping the
attribute on the floor. Since I expect more procedure attributes that
cannot be reflected in mlir::FunctionType will be needed for ABI,
optimizations, or debug info, this NFC patch adds a new enum attribute
to keep track of procedure attributes in the IR.

This patch is not updating lowering to lower more attributes, this will
be done in a separate patch to keep the test changes low here.

Adding the attribute on fir.dispatch and func.func will also be done in
separate patches.

0 files changed, 0 insertions, 0 deletions