Respect db_home setting even for SYSTEM/Microsoft accounts

We should not blindly set the home directory of the SYSTEM account (or
of Microsoft accounts) to `/home/<name>`, especially
`/etc/nsswitch.conf` defines `db_home: env`, in which case we want to
respect the `HOME` variable.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

winsup/cygwin/uinfo.cc

@@ -2240,7 +2240,11 @@ pwdgrp::fetch_account_from_windows (fetch_user_arg_t &arg, cyg_ldap *pldap)
 	 it to a well-known group here. */
       if (acc_type == SidTypeUser
 	  && (sid_sub_auth_count (sid) <= 3 || sid_id_auth (sid) == 11))
-	acc_type = SidTypeWellKnownGroup;
+	{
+	  acc_type = SidTypeWellKnownGroup;
+	  home = cygheap->pg.get_home ((PUSER_INFO_3) NULL, sid, dom, name,
+				       fully_qualified_name);
+	}
       switch ((int) acc_type)
 	{
 	case SidTypeUser: