[InstCombine] Transform (A + B) - (A & B) to A | B (PR48604)

define i32 @src(i32 %x, i32 %y) {
%0:
  %a = add i32 %x, %y
  %o = and i32 %x, %y
  %r = sub i32 %a, %o
  ret i32 %r
}
=>
define i32 @tgt(i32 %x, i32 %y) {
%0:
  %b = or i32 %x, %y
  ret i32 %b
}
Transformation seems to be correct!

https://alive2.llvm.org/ce/z/2fhW6r