0a3a397481
RCCL uses -fgpu-rdc to compile its source objects. When linking
the RCCL static library, the link and archive step must do through
hipcc and uses the flag --emit-static-lib. When compiling
UnitTests, the librccl.a must be consumed through -l and -L.
[ROCm/rccl commit: 958b213428]