powerpc/configs: Drop removed CONFIG_LOGFS

In commit 1d0fd57a ("logfs: remove from tree"), logfs was removed
from the tree, so we can drop it from our defconfigs.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/configs/ppc44x_defconfig

@@ -94,7 +94,6 @@ CONFIG_PROC_KCORE=y
 CONFIG_TMPFS=y
 CONFIG_JFFS2_FS=y
 CONFIG_UBIFS_FS=m
-CONFIG_LOGFS=m
 CONFIG_CRAMFS=y
 CONFIG_SQUASHFS=m
 CONFIG_SQUASHFS_XATTR=y