Remove support for Windows versions without ICU

We now require Windows 10 version 1903, which comes bundled with ICU.

README.md

@@ -5,6 +5,8 @@
 
 This project comprises a collection of scripts to build a modern GNUstep toolchain for x64 or arm64 architectures using the Visual Studio toolchain and LLVM/Clang. The toolchain supports Objective-C 2.0 features like blocks and Automatic Reference Counting (ARC) and can be used to integrate Objective-C code in any native Windows app — including Visual Studio projects — using LLVM/Clang (without using MinGW).
 
+The toolchain supports Windows 10 version 1903 or later.
+
 
 ## Libraries
 
@@ -19,7 +21,6 @@ The toolchain consists of the following libraries:
 - [libxml2](https://github.com/GNOME/libxml2)
 - [libxslt](https://github.com/GNOME/libxslt)
 - [libcurl](https://github.com/curl/curl)
-- [ICU](https://docs.microsoft.com/en-us/windows/win32/intl/international-components-for-unicode--icu-) (using system-provided DLL on Windows 10 version 1903 or later)
 
 
 ## Installation

phases/16-libxml2.bat

@@ -14,16 +14,6 @@ for /f "usebackq delims=" %%i in (`call %BASH% '../scripts/get-latest-github-rel
 call "%~dp0\..\scripts\common.bat" prepare_project || exit /b 1
 
 cd "%SRCROOT%\%PROJECT%" || exit \b 1
-
-:: check which ICU libraries to link
-if exist "%INSTALL_PREFIX%\lib\icuin.lib" (
-  set "LIBS_PRIVATE=-licuin -licuuc -licudt"
-) else (
-  echo Using system-provided ICU DLL ^(requires Windows 10 version 1903 or later^)
-  git apply "%ROOT_DIR%\patches\opt-libxml2-windows-icu.patch" || exit /b 1
-  set "LIBS_PRIVATE=-licu"
-)
-
 cd "win32" || exit /b 1
 
 echo.
@@ -55,4 +45,4 @@ xcopy /Y /F "bin.msvc\libxml2_a.lib" "%INSTALL_PREFIX%\lib\xml2.lib*" || exit /b
 xcopy /Y /F "%SRCROOT%\%PROJECT%\include\libxml\*.h" "%INSTALL_PREFIX%\include\libxml\" || exit /b 1
 
 :: write pkgconfig file
-call "%~dp0\..\scripts\common.bat" write_pkgconfig libxml-2.0 %TAG% -DLIBXML_STATIC -lxml2 "%LIBS_PRIVATE%" || exit /b 1
+call "%~dp0\..\scripts\common.bat" write_pkgconfig libxml-2.0 %TAG% -DLIBXML_STATIC -lxml2 -licu || exit /b 1