Align include guards with OpenOCD coding guidelines

[TommyMurphyTM1234]

Third attempt after these two abortive attempts failed due to checkpatch and git complexity:

• Align include guards with OpenOCD coding guidelines. #1103
• Align RISC-V target header file include guards with OpenOCD coding style guide #1102

Fixes:

• Some header guards do not comply to style guide #1097

These include files have not been changed because they are programmatically generated elsewhere so any changes to their content would need to be done there and not here:

• riscv-openocd/src/target/riscv/debug_defines.h

  Lines 1 to 4 in f5f5f6d

  	/*
  	* This file is auto-generated by running 'make debug_defines' in
  	* https://github.com/riscv/riscv-debug-spec/ (40b9a05)
  	*/

• riscv-openocd/src/target/riscv/encoding.h

  Lines 5 to 8 in f5f5f6d

  	/*
  	* This file is auto-generated by running 'make' in
  	* https://github.com/riscv/riscv-opcodes (ed68c21)
  	*/

[TommyMurphyTM1234]

Check Code Style (checkpatch) / check (pull_request) Successful in 19s

Phew!

[en-sc]

LGTM, thanks for the patch!
Sorry for all the trouble with the Checkpatch.

[TommyMurphyTM1234]

Thanks @en-sc - sorry about all the confusion with the earlier PRs.

[aap-sc]

@en-sc , @TommyMurphyTM1234 and I'm just sorry that I still haven't debugged #1049

[aap-sc]

@JanMatCodasip , @MarekVCodasip FYI. Unless there is no objection in a day or two - I'm going to merge this one.