[OpenCL] Fix whitespace

4 jobs for master in 2 minutes and 12 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  Build
passed #32559488
clang-cuda

00:02:09

passed #32559490
clang-nocuda

00:02:01

passed #32559484
gcc-cuda

00:02:12

passed #32559486
gcc-nocuda

00:01:52