floss: shift MGMT opcodes

This patch shifts the MGMT opcodes for floss starting from 0x0100
so that they do not conflict with the upstream regular MGMT opcodes
in the future.

Bug: 263764771
Tag: #floss
Test: Manual test on a ChromeOS device

Change-Id: I46d3740c1809233e54e95e1818e10f25810e417e