A write to CSSELR needs to complete before its results can be observed
via CCSIDR. So add a ISB to ensure that this is the case.
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>