Try to fix AppVeyor CMake stub

.appveyor.yml

@@ -30,7 +30,7 @@ test_script:
 
 - cmd: >-
 
-    IF "%BUILD_MODE%"=="CMake" (
+    if($env:BUILD_MODE -eq "CMake") {
 
         mkdir cmake-build
 
@@ -38,7 +38,7 @@ test_script:
 
         cmake ../
 
-    ) else (
+    } else {
 
         msbuild /t:Build /p:platform=%platform%;configuration=%configuration% cryptlib.vcxproj
 
@@ -50,7 +50,7 @@ test_script:
 
         cryptest.exe tv all
 
-    )
+    }
 
 notifications:
   - provider: Email

CMakeLists.txt

@@ -358,7 +358,7 @@ if (("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang") OR ("${CMAKE_CXX_COMPILER_ID}"
 	if (("${CRYPTOPP_X86_64}" STREQUAL "1") OR ("${CRYPTOPP_I386}" STREQUAL "1") OR ("${CRYPTOPP_X32}" STREQUAL "1"))
 
 		CHECK_CXX_COMPILER_FLAG("-mssse3" CRYPTOPP_IA32_SSSE3)
-		CHECK_CXX_COMPILER_FLAG("-msse4" CRYPTOPP_IA32_SSE4)
+		CHECK_CXX_COMPILER_FLAG("-msse4.2" CRYPTOPP_IA32_SSE4)
 		CHECK_CXX_COMPILER_FLAG("-mssse3 -mpclmul" CRYPTOPP_IA32_CLMUL)
 		CHECK_CXX_COMPILER_FLAG("-msse4.1 -maes" CRYPTOPP_IA32_AES)
 		CHECK_CXX_COMPILER_FLAG("-msse4.2 -msha" CRYPTOPP_IA32_SHA)