Fix vulkan link to on cfgmgr32 case-sensitive fs

On MinGW from Linux this fails because cfgmgr32 is lowercase. This will still work on win32.
diff --git a/loader/CMakeLists.txt b/loader/CMakeLists.txt
index f16c014..7341403 100644
--- a/loader/CMakeLists.txt
+++ b/loader/CMakeLists.txt
@@ -228,7 +228,7 @@
         target_link_libraries(vulkan OneCoreUAP.lib LIBCMT.LIB LIBCMTD.LIB LIBVCRUNTIME.LIB LIBUCRT.LIB)
         set_target_properties(vulkan PROPERTIES LINK_FLAGS "/NODEFAULTLIB")
     else()
-        target_link_libraries(vulkan Cfgmgr32)
+        target_link_libraries(vulkan cfgmgr32)
     endif()
 
     add_dependencies(vulkan loader_asm_gen_files)