kernel: Move to Linux 4.18.3-openpower1

Update to 4.18, and re-generate the defconfig. In addition, make the
following changes:

 - Enable EXPERT, so we can disable some things
 - Disable non-powerpc BPF decoders
 - Disable TASKSTATS
 - Disable unused syscalls
 - Set more things to be modules
 - Turn off unused network vendors

Note that CONFIG_I2C_CHARDEV=y as the module is not loaded
automatically, and without this i2cget etc. will fail.

Buildroot is updated to include support for v4.18.

Signed-off-by: Joel Stanley <joel@jms.id.au>

1 files changed, 0 insertions, 0 deletions

diff --git a/buildroot b/buildroot
-Subproject c99f2eeb8cc85e36a34a957b57cfbba9647d262
+Subproject 4f66fd5bf4a8e64b9d39db0c74d07684bacda07