[GridLaunch] Fixes for anonymous namespace types

[kwu91]

Types in anonymous namespaces are labeled with "(anonymous namespace)" string. This PR resolves the parenthesis and space characters when generating the GridLaunch wrapper.

Clang will sometimes mark the kernel function with InternalLinkage if the arguments contain types in anonymous namespaces. This will interfere with the opt passes in clamp-link. This PR also resolves that issue by forcing GridLaunch kernel functions to the default ExternalLinkage.

Finally, this PR adds some additional debugging information when a type is unknown.

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Tests:

ROCK: master/b0b2dee
ROCR: master/de0d9b5

Failing Tests (4):                        
    CPPAMP :: Unit/HC/memcpy_symbol1.cpp  
    CPPAMP :: Unit/HC/memcpy_symbol3.cpp  
    CPPAMP :: Unit/HC/wg_size.cpp         
    CPPAMP :: Unit/HSAIL/shfl_xor.cpp     

  Expected Passes    : 663                
  Expected Failures  : 25                 
  Unsupported Tests  : 10                 
  Unexpected Failures: 4                  

master also seems to have the same failure rate.

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HIP-privatestaging: privatestaging/31dc13d2
HIP-Examples-privatestaging: privatestaging/23c7882

All tests passed, except for hipHostRegister. Expected fail.
All examples passed.