eltwise: pow: if beta is not equal to 0, 0.5, 1, 2, oneDNN does not work properly.

[kawakami-k]

Summary

If beta is not equal to 0, 0.5, 1, 2, eltwise: pow does not work properly.
x64's implementation calls powf() of math.h. For aarch64, Register store/load part needs to be fixed before/after powf() is called.

Version

dnnl_verbose,info,oneDNN v1.6.0 (commit 5dca2008255a281b3d0a600036504a1aabd490d3)
dnnl_verbose,info,cpu,runtime:OpenMP
dnnl_verbose,info,cpu,isa:Generic
dnnl_verbose,info,gpu,runtime:none
dnnl_verbose,exec,cpu,reorder,simple:any,undef,src_f32::blocked:abc:f0 dst_f32::blocked:abc:f0,,,5x16x3,0.794922

Steps to reproduce

cmake .. -DDNNL_INDIRECT_JIT_AARCH64=ON          
./benchdnn --eltwise --alg=pow --alpha=0 --beta=1.5 5x16x3
zsh: segmentation fault (core dumped)  ./benchdnn --eltwise --alg=pow --alpha=0 --beta=1.5 5x16x3