licenses, AboutSystem: Add credits for netresolv.

* Add the ISC license; it's similar to the MIT license but isn't
   worded identically, and it's referenced from netresolv.

 * Drop the "Berkeley" license, it was used for an older version
   of the NetBSD credits, and is just the 3-clause BSD anyway, it appears.

data/system/data/licenses/Berkeley

@@ -1,27 +0,0 @@
-Copyright (c) <year>
-     The Regents of the University of California.  All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions
-are met:
-
-  1. Redistributions of source code must retain the above copyright
-     notice, this list of conditions and the following disclaimer.
-  2. Redistributions in binary form must reproduce the above copyright
-     notice, this list of conditions and the following disclaimer in the
-     documentation and/or other materials provided with the distribution.
-  3. Neither the name of the University nor the names of its contributors
-     may be used to endorse or promote products derived from this software
-     without specific prior written permission.
-
-THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 
-ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
-FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
-OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS  INTERRUPTION)
-HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
-OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
-SUCH DAMAGE.

data/system/data/licenses/ISC

@@ -0,0 +1,13 @@
+Copyright (c) <year>, <copyright holder>
+
+Permission to use, copy, modify, and/or distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

src/apps/aboutsystem/AboutSystem.cpp

@@ -1806,6 +1806,19 @@ AboutView::_CreateCreditsView()
 		StringVector(),
 		"https://www.freebsd.org");
 
+	// NetBSD copyrights
+	AddCopyrightEntry("The NetBSD Project",
+		B_TRANSLATE("Contains software developed by the NetBSD "
+		"Foundation, Inc. and its contributors:\n"
+		"netresolv\n"
+		COPYRIGHT_STRING "1998-2023 The NetBSD Project, "
+		COPYRIGHT_STRING "2004-2009 by Internet Systems Consortium, Inc. (\"ISC\"), "
+		COPYRIGHT_STRING "1996-2003 by Internet Software Consortium. "
+		"All rights reserved."),
+		StringVector("ISC", kBSDTwoClause, kBSDThreeClause, NULL),
+		StringVector(),
+		"https://www.netbsd.org");
+
 	// FFmpeg copyrights
 	_AddPackageCredit(PackageCredit("FFmpeg")
 		.SetCopyright(B_TRANSLATE(COPYRIGHT_STRING "2000-2019 Fabrice "