arm: Update infocenter.arm.com URLs

arm: Update infocenter.arm.com URLs

Update infocenter.arm.com URLs for various pieces of Arm
documentation to the new developer.arm.com equivalents.  (There is a
redirection in place from the old URLs, but we might as well update
our comments in case the redirect ever disappears in future.)

This patch covers all the URLs which are not MPS2/SSE-200/IoTKit
related (those are dealt with in a different patch).

Signed-off-by: Peter Maydell <[email protected]>
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Tested-by: Philippe Mathieu-Daudé <[email protected]>
Message-id: 20210205171456[email protected]