d: Merge upstream dmd, druntime 4ca4140e58, phobos 454dff14d.

D front-end changes:

	- Import dmd v2.103.0-beta.1.
	- Using `alias this' for classes has been deprecated.
	- The feature `-fpreview=dip25` is now enabled by default.
	- The compile-time traits `isVirtualFunction' and
	  `getVirtualFunctions' have been deprecated.

D runtime changes:

	- Import druntime v2.103.0-beta.1.

Phobos changes:

	- Import phobos v2.103.0-beta.1.
	- Updated unicode grapheme walking updated to conform to Unicode
	  version 15.
	- Improved friendliness of error messages when instantiating
	  `std.algorithm.iteration.joiner' and
	  `std.algorithm.sorting.sort' with wrong inputs.

gcc/d/ChangeLog:

	* dmd/MERGE: Merge upstream dmd 4ca4140e58.
	* dmd/VERSION: Bump version to v2.103.0-beta.1.
	* Make-lang.in (D_FRONTEND_OBJS): Add d/errorsink.o.
	* d-ctfloat.cc (CTFloat::sprint): Update signature for new front-end
	interface.
	* d-frontend.cc (getTypeInfoType): Likewise.
	* d-lang.cc (d_handle_option): Remove handling of -fpreview=dip25 and
	-frevert=dip25.
	(d_post_options): Remove enabling of sealed references language
	feature when scoped pointers is enabled.
	* d-tree.h (create_typeinfo): Update signature.
	* decl.cc (DeclVisitor::finish_vtable): Update for new front-end
	interface.
	(DeclVisitor::visit (VarDeclaration *)): Likewise.
	(DeclVisitor::visit (FuncDeclaration *)): Check skipCodegen to see if
	front-end explicitly requested not to generate code.
	* expr.cc (ExprVisitor::visit (NewExp *)): Update for new front-end
	interface.
	* lang.opt (fpreview=dip25): Remove.
	(frevert=dip25): Remove.
	* modules.cc (layout_moduleinfo_fields): Update for new front-end
	interface.
	(layout_moduleinfo): Likewise.
	* runtime.def (NEWCLASS): Remove.
	* toir.cc (IRVisitor::visit (IfStatement *)): Don't generate IR for if
	statement list when condition is `__ctfe'.
	* typeinfo.cc (create_typeinfo): Add generate parameter.
	* types.cc (layout_aggregate_members): Update for new front-end
	interface.

libphobos/ChangeLog:

	* libdruntime/MERGE: Merge upstream druntime 4ca4140e58.
	* libdruntime/Makefile.am (DRUNTIME_DSOURCES): Add core/factory.d.
	* libdruntime/Makefile.in: Regenerate.
	* src/MERGE: Merge upstream phobos 454dff14d.
	* testsuite/libphobos.hash/test_hash.d: Update test.
	* testsuite/libphobos.shared/finalize.d: Update test.
	* libdruntime/core/factory.d: New file.

gcc/testsuite/ChangeLog:

	* gdc.dg/torture/simd23084.d: New test.
	* gdc.dg/torture/simd23085.d: New test.
	* gdc.dg/torture/simd23218.d: New test.