buildenv/1.3.x: fix LNK4099 warning when linking to protobuf

libprotobuf.lib(message_lite.cc.obj) : warning LNK4099: PDB 'vc140.pdb' was not found with 'libprotobuf.lib(message_lite.cc.obj)' or at 'D:\a\1\s\release\vc140.pdb'; linking object as if no debug info
LINK : error LNK1218: warning treated as error; no output file generated

buildenv/1.3.x/win32-static/patches/protobuf-missing-pdb-fix.patch

@@ -0,0 +1,11 @@
+--- cmake/CMakeLists_txt
++++ cmake/CMakeLists.txt
+@@ -133,6 +133,8 @@
+ endif (protobuf_BUILD_SHARED_LIBS)
+
+ if (MSVC)
++  # Bake debug info into the binaries
++  add_compile_options(/Z7)
+   # Build with multiple processes
+   add_definitions(/MP)
+   add_definitions(/wd4244 /wd4267 /wd4018 /wd4355 /wd4800 /wd4251 /wd4996 /wd4146 /wd4305)

buildenv/1.3.x/win32-static/protobuf.build

@@ -1,5 +1,5 @@
 #!/usr/bin/env mumble-build
-# Copyright 2013-2014 The 'mumble-releng' Authors. All rights reserved.
+# Copyright 2013-2020 The 'mumble-releng' Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that
 # can be found in the LICENSE file in the source tree or at
 # <http://mumble.info/mumble-releng/LICENSE>.
@@ -19,6 +19,10 @@ function extract {
 	cd protobuf-3.2.0
 }
 
+function prepare {
+	patch -p1 < ${MUMBLE_BUILDENV_ROOT}/patches/protobuf-missing-pdb-fix.patch
+}
+
 function build {
 	if [ "${MUMBLE_BUILD_CONFIGURATION}" == "Release" ]; then
 		BUILD_TYPE="RelWithDebInfo"