CMake: Install liblzma.pc even with MSVC

I had misunderstood that it wouldn't be useful with MSVC.
vcpkg had been installing liblzma.pc with custom rules since 2020,
years before liblzma.pc support was added to CMakeLists.txt.

See:
https://github.com/microsoft/vcpkg/blob/eb895b95aac6fd7485373702f29f508c42a180a0/ports/liblzma/portfile.cmake
microsoft/vcpkg#39024 (comment)

CMakeLists.txt

@@ -1411,11 +1411,9 @@ install(FILES "${CMAKE_CURRENT_BINARY_DIR}/liblzma-config.cmake"
         DESTINATION "${liblzma_INSTALL_CMAKEDIR}"
         COMPONENT liblzma_Development)
 
-if(NOT MSVC)
-    install(FILES "${CMAKE_CURRENT_BINARY_DIR}/liblzma.pc"
-            DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig"
-            COMPONENT liblzma_Development)
-endif()
+install(FILES "${CMAKE_CURRENT_BINARY_DIR}/liblzma.pc"
+        DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig"
+        COMPONENT liblzma_Development)
 
 
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