Change in flashrom[master]: buspirate_spi.c: Separate shutdown from failed init cleanup

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Nico Huber, Edward O'Callaghan, Angel Pons.
Anastasia Klimchuk has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/52877 )

Change subject: buspirate_spi.c: Separate shutdown from failed init cleanup
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Patch Set 1:

(1 comment)

File buspirate_spi.c:

https://review.coreboot.org/c/flashrom/+/52877/comment/9ef3d665_9008d396 
PS1, Line 672: 	if (register_shutdown(buspirate_spi_shutdown, NULL) != 0) {
             : 		ret = 1;
             : 		goto init_err_cleanup_exit;
             : 	}
After moving register_shutdown below this has the same situation as CB:52773 , specifically if register_shutdown fails than full cleanup is performed. I use the same approach as we agreed on CB:52773