tools/x86/kcpuid: Set parse_line() return type to void

tools/x86/kcpuid: Set parse_line() return type to void

parse_line() returns an integer but its caller ignored it. Change the
function signature to return void.

While at it, adjust some of the "Skip line" comments for readability.

Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20250324142042.29010-9-darwi@linutronix.de