Kernel prepatch 4.14-rc6

The 4.14-rc6 kernel prepatch is out. "rc6 is a bit larger than I was hoping for, and I'm not sure whetherthat is a sign that we _will_ need an rc8 after all this release(which wouldn't be horribly surprising), or whether it's simply due totiming. I'm going to leave that open for now, so just know that rc8_may_ happen."