[SPARC] Zero-extend the operands when doing UMULO on 64-bit integers

On SPARC, S/UMULO operation on 64-bit integers works by extending the value to 128-bit, then doing a multiplication and checking the upper half of the result.
This makes UMULO works correctly by putting a zero in the upper half rather than doing a sign extension.

Reviewed By: LemonBoy

Differential Revision: https://reviews.llvm.org/D110555