powerpc: Use the asm-generic versions of some uapi includes

These are completely obvious as all they do is include the asm-generic
versions.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>