d: Merge upstream dmd 4d1bfcf14, druntime 9ba9a6ae, phobos c0cc5e917.

D front-end changes:

    - Import dmd v2.099.1.
    - Added `@mustuse' attribute, implmenting DIP 1038.
    - Added `.tupleof` property for static arrays

D runtime changes:

    - Import druntime v2.099.1.

Phobos changes:

    - Import phobos v2.099.1.
    - Zlib bindings have been updated to 1.2.12.

gcc/d/ChangeLog:

	* Make-lang.in (D_FRONTEND_OBJS): Add d/common-bitfields.o,
	d/mustuse.o.
	* d-ctfloat.cc (CTFloat::isIdentical): Don't treat NaN values as
	identical.
	* dmd/MERGE: Merge upstream dmd 4d1bfcf14.
	* expr.cc (ExprVisitor::visit (VoidInitExp *)): New.

libphobos/ChangeLog:

	* libdruntime/MERGE: Merge upstream druntime 9ba9a6ae.
	* src/MERGE: Merge upstream phobos c0cc5e917.