Update createEdgeMask to created masks where the terminator in Src is a
switch. We need to handle 2 separate cases:
1. Dst is not the default desintation. Dst is reached if any of the
cases with destination == Dst are taken. Join the conditions for each
case where destination == Dst using a logical OR.
2. Dst is the default destination. Dst is reached if none of the cases
with destination != Dst are taken. Join the conditions for each case
where the destination is != Dst using a logical OR and negate it.
Edge masks are created for every destination of cases and/or
default when requesting a mask where the source is a switch.
Fixes https://github.com/llvm/llvm-project/issues/48188.
PR: https://github.com/llvm/llvm-project/pull/99808
