Sync asm/asm.h with Linux 5.7.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: Stefan Roese <sr@denx.de>

When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>

Update definitions for processor, registers as well as assemby
macros.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>

Put all functions coded in assembly in sub-sections of
section .text. This allows the linker to garbage collect
unused assembly functions too.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>

Correctly annotate _start and relocate_code as functions to
produce more readable disassembly code generated by objdump.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>

Replace camel-case style with upper-case style globally.

Signed-off-by: Zhizhou Zhang <etou.zh@gmail.com>

This helps to clean up the include/ directory so that it only contains
non-architecture-specific headers and also matches Linux's directory
layout which many U-Boot developers are already familiar with.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>