Add call to early_memtest() so that kernel compiled with
CONFIG_MEMTEST really perform memtest at startup when requested
via 'memtest' boot parameter.
Tested-by: NDaniel Axtens <dja@axtens.net>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>