Remove hipblasComplex, hipblasDatatype and remove HIPBLAS_V2 API

[daineAMD]

Again, sorry for the huge PR, but with the testing infrastructure I found it difficult to split this into smaller PRs. Changes include:

• Client-side
  • remove hipblas_v2-test and hipblas_v2-bench along with infrastructure for this
  • use hipComplex directly for testing. Mostly renaming, but also needed to add/change a couple helpers
  • hipblasDatatype -> hipDatatype renaming
• Library-side
  • Remove all V2 APIs. Each function which previously contained a hipblasDatatype or hipblasComplex type had a V2 version
  • Change all APIs to match the V2 signature. I.e. change all hipblasDatatype -> hipDatatype and hipblasComplex -> hipComplex, along with hipblasDatatype -> hipblasComputeType_t for gemm_ex
  • Change Fortran API. This did not have a V2 version as mentioned in the initial deprecation

Any users who ignored the deprecation warning and have not been compiling with HIPBLAS_V2 defined will see breaking changes after this PR. If users have been using the HIPBLAS_V2 define, then they shouldn't see any changes.

Edit: I see cuda build is failing so might have a couple more changes coming.