Limit ConvOclDirectFwdGen solver for fp32 (#2105)
Limit ConvOclDirectFwdGen solver for fp32 (#2105)

* limit conv_fwd_dir_gen solver to c<=3 for fp32
* address review comments
ROCmSoftwarePlatform/MIOpen,ROCmSoftwarePlatform/MIOpen,ROCmSoftwarePlatform/MIOpen,ROCmSoftwarePlatform/MIOpen,ROCmSoftwarePlatform/MIOpen