fix CMake error
fix CMake error

```
CMake Error at cmake/alpakaCommon.cmake:498 (if):
  if given arguments:

    "(" "STREQUAL" "Debug" ")" "OR" "(" "STREQUAL" "RelWithDebInfo" ")"

  Unknown arguments specified
Call Stack (most recent call first):
  CMakeLists.txt:75 (include)

-- Configuring incomplete, errors occurred!
```

BenjaminW3/alpaka,BenjaminW3/alpaka