[compiler-rt] Fix cmake warnings

 - Fix cmake BOOL misspellings
 - Set cmake policy for CMP0075 to NEW

As requested by smeenai I've compared CMAkeCache.txt in master with and
without this patch and the only changes are to the variable types I fixed:

     $ diff build-b1-master/CMakeCache.txt build-b1-compiler-rt-fix-cmake-warnings/CMakeCache.txt
     503c503
     < COMPILER_RT_BAREMETAL_BUILD:STRING=OFF
     ---
     > COMPILER_RT_BAREMETAL_BUILD:BOOL=OFF
     550c550
     < COMPILER_RT_HWASAN_WITH_INTERCEPTORS:STRING=ON
     ---
     > COMPILER_RT_HWASAN_WITH_INTERCEPTORS:BOOL=ON

Patch by Wink Saville <wink@saville.com>.

Differential Revision: https://reviews.llvm.org/D61203

llvm-svn: 361866

compiler-rt/CMakeLists.txt

@@ -5,6 +5,10 @@
 
 cmake_minimum_required(VERSION 3.4.3)
 
+if(POLICY CMP0075)
+  cmake_policy(SET CMP0075 NEW)
+endif()
+
 # Check if compiler-rt is built as a standalone project.
 if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR OR COMPILER_RT_STANDALONE_BUILD)
   project(CompilerRT C CXX ASM)
@@ -61,10 +65,10 @@ if (NOT COMPILER_RT_ASAN_SHADOW_SCALE STREQUAL "")
       -D${COMPILER_RT_ASAN_SHADOW_SCALE_DEFINITION})
 endif()
 
-set(COMPILER_RT_HWASAN_WITH_INTERCEPTORS ON CACHE BOOLEAN
+set(COMPILER_RT_HWASAN_WITH_INTERCEPTORS ON CACHE BOOL
     "Enable libc interceptors in HWASan (testing mode)")
 
-set(COMPILER_RT_BAREMETAL_BUILD OFF CACHE BOOLEAN
+set(COMPILER_RT_BAREMETAL_BUILD OFF CACHE BOOL
   "Build for a bare-metal target.")
 
 if (COMPILER_RT_STANDALONE_BUILD)