Revert "This was missing the import"

I accidentally pushed this before review.

This reverts commit ea9b83ebfa2d009d1836fff2398f67bb58717d06.
diff --git a/External/SPEC/SpecCPU2017.cmake b/External/SPEC/SpecCPU2017.cmake
index 0b3241c..17f7b3d 100644
--- a/External/SPEC/SpecCPU2017.cmake
+++ b/External/SPEC/SpecCPU2017.cmake
@@ -4,7 +4,6 @@
 include(External)
 include(CopyDir)
 include(Host)
-include(CheckTypeSize)
 
 # Search for SPEC CPU 2017 root directory.
 llvm_externals_find(TEST_SUITE_SPEC2017_ROOT "speccpu2017" "SPEC CPU2017")