[Hexagon][NFC] Remove redundant condition
Condition secondReg is checked both in an outer and in an inner if
statement in static function canCompareBeNewValueJump() in file
HexagonNewValueJump.cpp. This patch removes the redundant inner check.
The issue was found using clang-tidy check under review
misc-redundant-condition. See https://reviews.llvm.org/D81272.
Differential Revision: https://reviews.llvm.org/D82556