[OpenMP] Add debug info about CC incompatibility

[markdewing]

Summary

Add a debug message with the compute capability of the device
and the image when they're not compatible.

[markdewing]

Add the debug message to the new plugin

openmp/libomptarget/plugins/cuda/src/rtl.cpp

 //===----RTLs/cuda/src/rtl.cpp - Target RTLs Implementation ------- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
if (cuDeviceGetAttribute(&Minor,
                              CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MINOR,
                              Device) != CUDA_SUCCESS)
       return false;
 
     // A cubin generated for a certain compute capability is supported to run on
     // any GPU with the same major revision and same or higher minor revision.
     int32_t ImageMajor = ArchStr[0] - '0';
     int32_t ImageMinor = ArchStr[1] - '0';
-    if (Major != ImageMajor || Minor < ImageMinor)
+    if (Major != ImageMajor || Minor < ImageMinor) {
+      DP("Compute capability of image not compatible with device. Device: %d "
+         "%d "
+         "Image: %d %d\n",
+         Major, Minor, ImageMajor, ImageMinor);
       return false;
     }
+  }
 
   DP("Image has compatible compute capability: %s\n", Info->Arch);
   return true;
 }
 
 int32_t __tgt_rtl_number_of_devices() { return DeviceRTL.getNumOfDevices(); }
 
 int64_t __tgt_rtl_init_requires(int64_t RequiresFlags) {