AVR: Adhere to GNU coding style

This patch fixes some style nits:

- Fix indentations
- Using TABs for indentation
- Breaking long lines
- Remove ; after the closing } of a code block

bfd/
	* cpu-avr.c: Adhere to GNU coding style.
	* elf32-avr.c: Same.
	* elf32-avr.h: Same.

gas/
	* config/tc-avr.c: Adhere to GNU coding style.

opcodes/
	* avr-dis.c: Adhere to GNU coding style.

include/
	* opcode/avr.h: Adhere to GNU coding style.