powerpc/configs: Remove CMDLINE_BOOL

Regenerate defconfigs to remove CONFIG_CMDLINE_BOOL and the default
CONFIG_CMDLINE where applicable.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200611224220.25066-3-chris.packham@alliedtelesis.co.nz