Convert license tags to SPDX identifiers

This commit also converts our own copyright headers to directly use
SPDX, but leaves all other copyright header intact, only adding the
SPDX ident. As far as possible this commit also merges multiple
Data61 copyright statements/headers into one for consistency.

style: correct parenthesis padding

Use astyle's unpad-paren to unpad all parentheses that are not included
by pad-header, pad-oper, and pad-comma.

serial-refactor: Fixed circular includes

Modify hardware_gen script to only include chosen
serial path. Added newlines to serial drivers to fix
concat issues when compiling. Move cmake macro RegisterDriver
up a level to support timer refactor. Modify arm cmake to reflect
this.

serial-input: Remove whitespace

serial-input: Move UART_REG macro to the same place in every file

serial-refactor: Update config.cmake and rename drivers

Updated config.cmake in drivers/serial to use the marco properly
and added license. Renamed all serial drivers to conform to style.
Moved include for configurations scripts below tools used by the kernel.