Sanitise includes across codebase ...

Enforce full include path for includes. Deprecate old paths.

The following folders inside include/lib have been left unchanged:

- include/lib/cpus/${ARCH}
- include/lib/el3_runtime/${ARCH}

The reason for this change is that having a global namespace for
includes isn't a good idea. It defeats one of the advantages of having
folders and it introduces problems that are sometimes subtle (because
you may not know the header you are actually including if there are two
of them).

For example, this patch had to be created because two headers were
called the same way: e0ea0928d5b7 ("Fix gpio includes of mt8173 platform
to avoid collision."). More recently, this patch has had similar
problems: 46f9b2c3a282 ("drivers: add tzc380 support").

This problem was introduced in commit 4ecca33988b9 ("Move include and
source files to logical locations"). At that time, there weren't too
many headers so it wasn't a real issue. However, time has shown that
this creates problems.

Platforms that want to preserve the way they include headers may add the
removed paths to PLAT_INCLUDES, but this is discouraged.

Change-Id: I39dc53ed98f9e297a5966e723d1936d6ccf2fc8f
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

Merge pull request #1699 from chandnich/sgi-mt-support ...

Add support to implement multi-threaded platforms for SGI

plat/arm: remove weak implemention of 'plat_arm_psci_override_pm_ops' function ...

In order to allow Arm platforms to override the default list of PSCI
callbacks, remove the existing weak implementation of
'plat_arm_psci_override_pm_ops' function and let all the Arm platforms
implement their own 'plat_arm_psci_override_pm_ops' function.

For platforms that support SCMI protocol, the function
'css_scmi_override_pm_ops' can be additionally used as well to
override the default PSCI callbacks.

Change-Id: If7c27468bd51a00ea9c2a3716b5894163f5a9f3c
Signed-off-by: Chandni Cherukuri <chandni.cherukuri@arm.com>

plat/css: allow platforms to define the system power domain level ...

The CSS_SYSTEM_PWR_DMN_LVL macro that defines the system power domain
level is fixed at ARM_PWR_LVL2 for all CSS platforms. However, the
system power domain level can be different for CSS platforms that
use multi-threaded CPUs.

So, in preparation towards adding support for platforms that use
multi-threaded CPUs, refactor the definition of CSS_SYSTEM_PWR_DMN_LVL
such that CSS_SYSTEM_PWR_DMN_LVL is uniquely defined for each of the
CSS platform.

Change-Id: Ia837b13f6865e71da01780993c048b45b7f36d85
Signed-off-by: Chandni Cherukuri <chandni.cherukuri@arm.com>

Standardise header guards across codebase ...

All identifiers, regardless of use, that start with two underscores are
reserved. This means they can't be used in header guards.

The style that this project is now to use the full name of the file in
capital letters followed by 'H'. For example, for a file called
"uart_example.h", the header guard is UART_EXAMPLE_H.

The exceptions are files that are imported from other projects:

- CryptoCell driver
- dt-bindings folders
- zlib headers

Change-Id: I50561bf6c88b491ec440d0c8385c74650f3c106e
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

plat/arm: Introduce the N1SDP. ...

This patch adds support for the N1SDP (NeoVerse N1 System Development
Platform). It is an initial port and additional features are expected
to be added later.

The port includes only BL31 support as the System Control Processor
(SCP) is expected to take the role of primary boatloader

Change-Id: Ife17d8215a7bfcc1420204a72205e7ef920d0c10
Signed-off-by: Deepak Pandey <Deepak.Pandey@arm.com>