[lldb][DWARFExpression] Fix DW_OP_div to use signed division

This patch resolves an issue where a value
is incorrectly displayed if it is represented
by DW_OP_div.

This issue is caused by lldb evaluating
operands of DW_OP_div as unsigned
and performed unintended unsigned
division.

This issue is resolved by creating two
temporary signed scalar and performing
signed division.

(Addresses GH#61727)

Differential Revision: https://reviews.llvm.org/D147370