powerpc/configs: Update for CONFIG_SND changes

Commit eb3b705a ("ALSA: Make CONFIG_SND_OSSEMUL user-selectable")
means we need to set CONFIG_SND_OSSEMUL in our configs, otherwise we
lose some of the SND symbols.

And commit 0181307a ("ALSA: seq: Reorganize kconfig and build")
reorganised things, which causes the churn.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>