Fix the build for mingw and CMake + VStudio

Changes to the build to add the new Win32 Crypto API's inadvertently broke
the build for mingw and Visual Studio builds when generated by CMake.

Signed-off-by: Simon Butcher <simon.butcher@arm.com>
diff --git a/library/CMakeLists.txt b/library/CMakeLists.txt
index 83204f3..6215077 100644
--- a/library/CMakeLists.txt
+++ b/library/CMakeLists.txt
@@ -213,7 +213,7 @@
 endif()
 
 if(WIN32)
-    set(libs ${libs} ws2_32)
+    set(libs ${libs} ws2_32 bcrypt)
 endif(WIN32)
 
 if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")