The operation computes pow(b, p), where 'b' is floating point
and 'p' is a signed integer. The result's type matches 'b' type.
The operands must have the same shape.
Differential Revision: https://reviews.llvm.org/D129811
Precursor: https://reviews.llvm.org/D110200
Removed redundant ops from the standard dialect that were moved to the
`arith` or `math` dialects.
Renamed all instances of operations in the codebase and in tests.
Reviewed By: rriddle, jpienaar
Differential Revision: https://reviews.llvm.org/D110797
