drivers/base: cacheinfo: validate device node for all the caches

On architectures that depend on DT for obtaining cache hierarcy, we need
to validate the device node for all the cache indices, failing to do so
might result in wrong information being exposed to the userspace.

This is quite possible on initial/incomplete versions of the device
trees. In such cases, it's better to bail out if all the required device
nodes are not present.

This patch adds checks for the validation of device node for all the
caches and doesn't initialise the cacheinfo if there's any error.

Change-Id: Iab208708600589d9ef99d5fa5300c6d2ede2f2a0
Reported-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: stable <stable@vger.kernel.org> # 4.0
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Git-commit: 8a7d95f95c95f396decbd4cda6d4903fc4664946
Git-repo: https://source.codeaurora.org/quic/la/kernel/msm-4.9


Signed-off-by: Teng Fei Fan <tengfei@codeaurora.org>