Fix Windows dependency library names

Author: hughbe

cmake/modules/AddSwift.cmake

@@ -951,10 +951,17 @@ function(_add_swift_library_single target name)
   set(prefixed_link_libraries)
   foreach(dep ${SWIFTLIB_SINGLE_LINK_LIBRARIES})
     if("${dep}" MATCHES "^clang")
-      set(dep "${LLVM_LIBRARY_OUTPUT_INTDIR}/lib${dep}.a")
-    endif()
-    if("${dep}" STREQUAL "cmark")
-      set(dep "${CMARK_LIBRARY_DIR}/lib${dep}.a")
+      if("${SWIFT_HOST_VARIANT_SDK}" STREQUAL "WINDOWS")
+        set(dep "${LLVM_LIBRARY_OUTPUT_INTDIR}/${dep}.lib")
+      else()
+        set(dep "${LLVM_LIBRARY_OUTPUT_INTDIR}/lib${dep}.a")
+      endif()
+    elseif("${dep}" STREQUAL "cmark")
+      if("${SWIFT_HOST_VARIANT_SDK}" STREQUAL "WINDOWS")
+        set(dep "${CMARK_LIBRARY_DIR}/${dep}.lib")
+      else()
+        set(dep "${CMARK_LIBRARY_DIR}/lib${dep}.a")
+      endif()
     endif()
     list(APPEND prefixed_link_libraries "${dep}")
   endforeach()