[AMDGPU] Expand not pattern according to the XOR node divergence

[AMDGPU] Expand not pattern according to the XOR node divergence

The "not" is defined as XOR $src -1.
 We need to transform this pattern to either S_NOT_B32 or V_NOT_B32_e32
 dependent on the "xor" node divergence.

Reviewed By: rampitec, foad

Differential Revision: https://reviews.llvm.org/D115884