CI: always install llvm for MSYS2

Due to some recent package splits llvm is no longer installed
when clang is installed and the meson test suite was depending
on the transitive dependency.

Instead explicitly install llvm in all cases.

.github/workflows/msys2.yml

@@ -85,6 +85,7 @@ jobs:
             mingw-w64-${{ matrix.MSYS2_ARCH }}-python-pip
             mingw-w64-${{ matrix.MSYS2_ARCH }}-python-fastjsonschema
             mingw-w64-${{ matrix.MSYS2_ARCH }}-objfw
+            mingw-w64-${{ matrix.MSYS2_ARCH }}-llvm
             mingw-w64-${{ matrix.MSYS2_ARCH }}-${{ matrix.TOOLCHAIN }}
 
       - name: Install dependencies

test cases/frameworks/15 llvm/test.json

@@ -2,9 +2,9 @@
   "matrix": {
     "options": {
       "method": [
-        { "val": "config-tool", "expect_skip_on_jobname": ["msys2-gcc"] },
-        { "val": "cmake", "expect_skip_on_jobname": ["msys2-gcc"] },
-        { "val": "combination", "expect_skip_on_jobname": ["msys2-gcc"] }
+        { "val": "config-tool" },
+        { "val": "cmake" },
+        { "val": "combination" }
       ],
       "link-static": [
         { "val": true, "expect_skip_on_jobname": ["arch", "opensuse", "linux-gentoo-gcc"] },