This patch documents the Solaris-specific D bootstrap requirements.

Tested by building and inspecting gccinstall.{pdf,info}.

Ok for trunk?

I've omitted the Darwin-specific stuff so far documented in PRs d/103577
and d/103578:

* needs --enable-libphobos
* top of gcc-11 branch only
* backport of -static-libphobos patch
* Darwin/i386 doesn't work at all

	Rainer

-- 
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Rainer Orth, Center for Biotechnology, Bielefeld University


2022-03-16  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

	gcc:
	PR d/103528
	* doc/install.texi (Tools/packages necessary for building GCC)
	(GDC): Document libphobos requirement.
	(Host/target specific installation notes for GCC, *-*-solaris2*):
	Document libphobos and GDC specifics.