Details:
- Placed optimized version of BLAS DGEMM, ZGEMM definitions under
BLIS_CONFIG_EPYC as they use gemm small which are defined only
for zen family configurations.
- Added code to query and set cntx in gemv and trsv framework before
cntx is referred for any function pointers to avoid querying
from NULL pointer.
AMD-Internal: [CPUPL-1562]
Change-Id: I977d028ec4ddb57dcdc70e443e7708f36c01cca9
33ddf2e448