JIT: Optimize "x & cns == cns" pattern

[EgorBo]

Noticed in #100999:

void Foo(int x)
{
    if ((x & 0xC000000) == 0xC000000)
        Console.WriteLine();
}

Codegen on arm64:

            and     w0, w1, #0xC000000
            mov     w1, #0xC000000
            cmp     w0, w1
            bne     G_M37282_IG05

Expected codegen:

            mov     w1, #0xC000000
            bics    wzr, w8, w1
            bne     G_M37282_IG05

x64 is suboptimal for it as well, current codegen:

       and      edx, 0xC000000
       cmp      edx, 0xC000000
       jne      SHORT G_M37282_IG04

^ should be not + test.

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[quantumhu]

Hi, I'd like to attempt this issue if no one else is, thanks!