gemm-vega64

Implement asm gemm on vega64 for 4096x4096 fp32 matrix

Results

v10 is the highest performing kernel

Card	Shader Clock	Memory Clock	TFLOPs (fp32)	TFLOPs Peak (fp32)	Efficiency
MI25	1500Mhz	945Mhz	10.6	12.3	86%
RXVega64	1630Mhz	945Mhz	11.2	13.35	84%
VegaFE

As the code is not written in pure isa, compiler tries to move instructions around causing drop in performance.