CUDA: add v10.1.243 for ppc64le (spack#18237)

Closes spack#18174 

@smarocchi @ax3l @svenevs 

The error message in spack#18174 isn't great, but I'm hoping that spack#18127 will improve that.

var/spack/repos/builtin/packages/cuda/package.py

@@ -30,7 +30,8 @@
         'Linux-x86_64': ('560d07fdcf4a46717f2242948cd4f92c5f9b6fc7eae10dd996614da913d5ca11', 'http://developer.download.nvidia.com/compute/cuda/10.2/Prod/local_installers/cuda_10.2.89_440.33.01_linux.run'),
         'Linux-ppc64le': ('5227774fcb8b10bd2d8714f0a716a75d7a2df240a9f2a49beb76710b1c0fc619', 'http://developer.download.nvidia.com/compute/cuda/10.2/Prod/local_installers/cuda_10.2.89_440.33.01_linux_ppc64le.run')},
     '10.1.243': {
-        'Linux-x86_64': ('e7c22dc21278eb1b82f34a60ad7640b41ad3943d929bebda3008b72536855d31', 'https://developer.download.nvidia.com/compute/cuda/10.1/Prod/local_installers/cuda_10.1.243_418.87.00_linux.run')},
+        'Linux-x86_64': ('e7c22dc21278eb1b82f34a60ad7640b41ad3943d929bebda3008b72536855d31', 'https://developer.download.nvidia.com/compute/cuda/10.1/Prod/local_installers/cuda_10.1.243_418.87.00_linux.run'),
+        'Linux-ppc64le': ('b198002eef010bab9e745ae98e47567c955d00cf34cc8f8d2f0a6feb810523bf', 'https://developer.download.nvidia.com/compute/cuda/10.1/Prod/local_installers/cuda_10.1.243_418.87.00_linux_ppc64le.run')},
     '10.0.130': {
         'Linux-x86_64': ('92351f0e4346694d0fcb4ea1539856c9eb82060c25654463bfd8574ec35ee39a', 'https://developer.nvidia.com/compute/cuda/10.0/Prod/local_installers/cuda_10.0.130_410.48_linux')},
     '9.2.88': {